NEED HELP Engine Replaced - Won't Start

Gaffer

Original poster
Member
Jul 20, 2019
16
So Cal
2006 Trailblazer EXT LS

My son mostly, and I replaced the original engine with a freshly rebuilt one, same year (4.2) - assembled block and head only. We have crank but no start. Vehicle ran fine before engine replacement (rod through engine block). We cleared codes and with no battery, shorted the battery cables together for about 5 minutes to reset/bleed down electronics in PCM. My main question is if I need to do something for the PCM to learn the various engine sensors, or some other initial process. We are brand new to working on computer controlled cars so the most basic things we might know should not be assumed. In fact, I'm only assuming the engine rebuild included the crank, cam and/or other sensors. I haven't researched where these sensors would be to even know if they are installed. We transferred the oil pan, valve cover and accessories from the original block to the new one. It's getting fuel at 55 psi.

We get the following 4 codes during crank:
1) U1000 ABS $29, Class 2 Data Link
2) U1000 XFER $1A, Class 2 Data Link Malfunction
3) U1301 XFER $1A, High
4) P0335 ENG $10, Crankshaft Position Sensor A Circuit Malfunction INTERMITTENT

I really appreciate you help,

John
 
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Mooseman

Moderator
Dec 4, 2011
25,262
Ottawa, ON
Once you do get it running, it will need a CASE relearn. However, it should still run without it.

Do a search on this site for 'crank.no Starr's using Google. Lots of thread on this or look in the engine FAQ. There is also our alumni May03lt on YouTube that hhas a video.on this.

However, the U codes are concerning to memeeting that the databus is causing some issues and communications bbetween the BCM and PCM isn't happening. Is the security light on?
 
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Gaffer

Original poster
Member
Jul 20, 2019
16
So Cal
No security light during crank, but I get the engine and brake lights. I'll research as you recommended.
 

mrrsm

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Welcome to GMT nation...

The U1000 is a serious problem because All Databus Communications become affected. In Essence... If the normal 0-7 Volts DC used by the Databus has been shorted either to Ground or to 12 Volts DC Power... you'll have to locate the Break or Short and affect repairs. Because you have only recently performed this Engine Swap... Start by systematically re-visiting each and every Harness Connector... starting with the PCM... and COMPLETELY REMOVE AND REPLACE EACH CONNECTOR.

It is entirely possibly that if there was any haste involved to get this job done quickly just after struggling with the Donor Engine Installation... that some of the Harness Wires either got Cut or Stretched or the Connectors picked up some Oil and Dirt Contamination that is preventing the 0-5 Databus Signaling from getting through.

Use some CRC Electric Circuit Solvent NOT Brake Solvent or WD-40 to thoroughly spray out both the Male and Female sides of each and every Module and Sensor Connector... allowing enough time for the solvent to evaporate before re-connecting all of them. Examine each Connector and observe the Wiring harnesses so as not to overlook any obvious broken or separated Wiring.

What follows is just an EXAMPLE for you to follow for a Diagnostic Path based upon the information listed in this PI. Please note that central to the concept of this troubleshooting issue is that the U1000 is present in each case. The technical issues involved are fairly well explained...and if nothing else... it will give you pause to consider what actions went on during the Engine Swap that may have either damaged or short-circuited the Class 2 Network of the Vehicle.

Talk with your son about going over the Entire Engine Harness... including that area of the 4WD TCCM Module as well. A Bright Flashlight and a Careful Examination may preclude having to do anything exotic to solve this problem as long as you are Systematic about doing so:

This Excerpted Information comes from "TV" ...via this Link:



2002 Chevrolet TrailBlazer - 4WD | Bravada, Envoy, TrailBlazer (VIN S/T) Service Manual | Document ID: 2220897
--------------------------------------------------------------------------------
#PIT3832D: ABS Red Brake SVC And 4WD Light On HVAC Blower Inoperative - keywords B1375 C0379 DTC HI2 HI4 ignition IPC L04 MIL on U1000 U1041 - (Jan 7, 2009)

Subject: ABS, Red Brake, SVC and 4WD Light On, HVAC Blower Inoperative

Models:

2004-2007 Buick Rainier
2002-2009 Chevrolet Trailblazer
2002-2009 GMC Envoy
2002-2004 Oldsmobile Bravada
--------------------------------------------------------------------------------
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Condition/Concern:
Vehicle may exhibit a combination or all of the following symptoms: ABS light on, Red BRAKE light on, Service 4WD light on, HVAC blower motor inoperative. Various DTCs may also be present.

Recommendation/Instructions:
Perform the following diagnostics to check for loss of battery voltage to the rear fuse block on circuit 300 ORN for the following fuses:

Note: Prior to proceeding forward with the information below, it is important to verify the voltage as indicated however it is equally important to verify the integrity of each circuit. This can be achieved by performing a voltage drop test or by adding a device to each circuit that will supply sufficient load to verify the circuit's integrity.

HVAC 30A, 4WD 15A, HVAC 1 10A, BRAKE 10A, TBC RUN 3A.

•Check circuit 300 ORN for battery voltage when the ignition key is in the RUN position.
•Check for battery voltage at the rear fuse block under the rear seat Connector C1 pin D9.
•If battery voltage IS NOT present at these locations, check for voltage at the ignition switch pin G for circuit 300 ORN.
•If battery voltage IS present at the ignition switch pin G, check circuit 300 for an open.
•If battery voltage IS NOT present at the ignition switch pin G, replace the ignition switch.


Note: This PI does not apply to the Saab 97x. The 97x has a unique ignition switch location and an electrical harness. With this new switch, the electrical center pin designations and the ignition switch connector is different. In the event the concern above is experienced in a Saab 97x, circuit 300 can be checked for integrity using the appropriate schematics in eSI.

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.

---------------------------------------------------------------------------------------
#PIT3154: All GM Vehicles Using Class 2 Communications Diagnostic Strategy for DTC U1000 or U1255 - kw BCM code EBTCM radio RIM - (Sep 10, 2004)

Subject: All GM Vehicles Using Class 2 Communications Diagnostic Strategy For DTC U1000 or U1255

Models: .
--------------------------------------------------------------------------------

The following diagnosis might be helpful if the vehicle exhibits the symptom described in the PI.

Condition/Concern:
DTC U1000 or U1255 set current or history, with or without other DTCs

Recommendation/Instructions:
DTC U1000 Class 2 Data Link

DTC U1255 Lost Communications

These DTCs set when the control module does not receive a message that it was expecting from another control module, and does not know which control module did not send that message.

•If the DTC U1000 or U1255 is set in history with other DTCs set current or history, diagnose the other DTCs first.
•If the DTC U1000 or U1255 set current, this usually indicates a module that is currently not communicating or a configuration issue.


For example, if the control module is configured for an option (ie: Onstar, Keyless Entry, Memory Mirrors, etc.) that the vehicle does not have, it may expect to receive a message regarding this missing feature. This would usually occur due to the control module being recently replaced and incorrectly setup.

•When the DTC U1000 or U1255 is current, the module that is not communicating may not even be listed on the Tech 2 on the Diagnostic Circuit Check/Class 2 Message Monitor list.
•If the DTC U1000 or U1255 has set in history without other DTCs, replacing the control module setting the DTC is most likely NOT the solution. The module that has set the code is looking for an input from another module that is not communicating. Since the module did not receive an input that it is expecting to see, it sets a U1000 or U1255 which indicates there was a loss of communications. Look at the customer’s complaint (ie: intermittent, erratic tachometer operation); this will probably be a better indication of the control module that is the source of the concern.

Please follow this diagnosis process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed. If these steps do not resolve the condition, please contact GM TAC for further diagnostic assistance.

Models:

(All GM vehicles using Class 2 communications)


The Attached Image shows the location and appearance of the "CKP" Crankshaft Position Sensor. In very rare instances... if the Cast-In Notched Reluctor Ring of the Crankshaft were to make Direct Contact with the very outer edge of the CKP Sensor Cylinder that creates the Square Wave Hall Effect Signal ... it could cause the H-E Signal to appear "Clipped"on the Oscilloscope as the Timing Signal to Fire the Spark Plugs ordered by the PCM will not function correctly. In such cases... the engine can stumble very badly and run very erratically.

One Last Suggestion:

Visit this Link and Download the Service Manual for BOTH your present SUV AND the Donor SUV the Replacement Engine Came from so you can seek to find any discrepancies between the two vehicles that might also help to explain these problems.

These GM OEM Digital Complete Service Manuals available at GMT Nation are the Brain Child of @Mooseman.... Just Follow his Instructions on this link to find and download whatever you need. :>)

Welcome Aboard!




CKPSENSOR42LGM.pngCKPSENSOR1.jpg
 
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Gaffer

Original poster
Member
Jul 20, 2019
16
So Cal
Update on worked done; no codes; crank but no start/spark.

The ignition starter switch was acting up - crank with key in run but not crank mode - intermittently. The switch acted up so we replaced it. It now acts normal.

We inspected all, we believe, harnesses and connections. I sprayed them all with the CRC electronics cleaner. We found 2 loose ground wires and tightened them. We found no obvious damage to wires/harnesses/sensors. We tried starting again and have crank but no start. All codes cleared and we can't get it to start and we don't get any new codes.

We checked the CPM. Got 12V+ on Red, and basically nothing on the other 2 wires. We assumed the CPM was bad for not throwing 5V, which I believe we were to see. No start, so checked voltages with new sensor, and we got the same measurements as the original one. I used a standard digital multi-meter - nothing fancy.

I checked every fuse with the meter and all checked fine. We're at a loss and hope you have a suggestion. I fear it might be time to take it to a shop, but I want that to be a last resort. Any suggestions?

Thanks,
John
 

mrrsm

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Oct 22, 2015
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You should be able to do this without tearing out the Center Console. Visit the Under-Dash area on the Passenger Side Transmission Hump. Use a Bright Flashlight to Illuminate the G-201 Ground Fastener that binds two Major Grounds Components to the SUV Center metal Body. Try examining and tightening that Small Fastener for being LOOSE (I think its either an 8mm or 10mm Bolt) and Spray that area down with the CRC Solvent and then TIGHTEN IT DOWN without Over-Torquing it.

This is Important:

There is a "Common Network Splice Comb" called SP-201 with Multiple Black Wires nested within that thing as well. This provides a common Ground for the Entire Front Cabin area for the Class 2 Network. In a "Worst Case Scenario"...Carefully Pull that "Splice Comb" apart and you will effectively disconnect everything off of the Network. Then... try Starting the Vehicle. If the SUV Starts... DO NOT BE TEMPTED TO RACE THE ENGINE UNTIL IT PROPERLY WARMS UP.

You probably have absolutely no Idea How Long that Engine has been sitting dormant with the Engine Oil Bleeding completely down and out of the Oil Galleries and Oil Pick Up Tube... perhaps for much longer than you might imagine. Give the Engine a Chance to "Limber Up" at LOW RPM.

If the Motor Starts and Runs nominally... Allow the Engine to Idle and take whatever Voltage Measurements and other Running Engine (Fluid Leaks, Etc.) Observations you need to make. Then Shut the Engine Down and consider Tracing out those Black Splice Comb Wires SP-201 ...one at a time until you can either Isolate the Damaged, Inoperative Module or determine whether or not the Black Wire Voltage is Higher than the acceptable 0-7 Volts DC expected on the Network, as it may be a circumstance where the Network has been Shorted to Positive 12 Volts DC .

Hopefully, using this technique with a DMM set to Volts DC ... it will help you to isolate which Module if any is causing all of this trouble, and show where the problem lies on the Network. This Video from @MAY03LT should be very helpful in locating where all of these items are that need your attention next:


If this works to ensure that your Code Reader is working correctly... and it happens to pick up another P0335 Code AND the Engine STILL won't Start.. Consider changing out the "CKP" Crank Positon Sensor... because if THAT Sensor cannot pick up the Hall Effect Signals caused by the Rotating Notches on the Crankshaft Reluctor Wheel, then the PCM will NOT be able send the Correct Spark In Time with the CPAS (Solenoid) AND CPS Sensor inputs... and of course ...the Engine will refuse to Start.
 
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mrrsm

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Here are Three Other “Cranks… No Start” Situations that may provide more clues if needed:



 

mrrsm

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Check Fuse #28 (PCM 1 - 15 Amp Fuse) as the PCM AND the Ignition Coils AND the EFIs ALL SHARE THE SAME FUSE. If One or More Coils has Dead Shorted... it can Kill Fuse #28 and the PCM will NOT allow the Start Run Circuit to Complete.

Also... I just re-read your Post #7 and IIANM, You're saying that the Engine Turns Over with the Key in the Ignition RUN Position...but NOT when the Key is Turned further to the Final START Position. Is that right? If so... what has probably happened (and YOU will NOT be the First if this turns out to be the case) is that When you Swapped in the New Ignition, you may have removed the Old Ignition Switch and tossed it...and then taken the New Ignition Switch right of the Box and Plugged it into the Harness connection(s) and plunked it into the Bottom of the Ignition Key Lock Block and then tried to start the Vehicle. Hopefully your New Ignition Switch is the OEM ACDelco Version ...and NOTHING Else.

What can happen here is that IF the New Ignition Switch was NOT properly "Tooth Aligned" to agree with the Internal Lock work underneath the Steering Column... OR... if the Ignition Key was NOT rotated Counter-Clockwise into its Normal OFF detente position... then Either One or Both of these Conditions WILL prevent their Correct Alignment of all the Internal Electrical Contacts inside of the New Switch.

Watch this Video for the "Teeth Re-Alignment Procedures" that will need to be followed ...AFTER you remove the New Ignition Switch... and also Re-Set the Ignition Key Lock-Work back into its OFF Position. Please remember that the Original Ignition Switch that was in there was FUBARed and therefore cannot be relied upon for this necessary "Teeth Re-Alignment Procedure":


And then Prepare yourself to listen to THE Most Irritating Voice in Human Existence from an "Ichabod Crane" Look-A-Like sort of Dude... Plus the sounds of the Birds, the Airplanes and the Fire Truck Sirens and Ignition Ke Bongs for some additional distractions. However... his information does have Value to suit your situational needs with the New Ignition Switch:

 
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So here's what happened to me 2007 Chevy trailblazer 4.2 l 102k miles the motor lets out. I put a new crate motor in it 35k Miles later catastrophic oil pump failure motor replaced under warranty. Started to have a no crank no start situation, intermittent, also some U1000 codes multiple, many codes /part failures... Long story short I got a brand new crate motor that won't run so one at a time I start fixing the parts that are throwing codes: VVT sensor, cam sensor, crank sensor, starter, ignition switch, starter relay, battery, get the truck running and trans cooler lines split I'm in rust belt, so I replaced with brand new lines after couple of days battery light comes on. Stop at AutoZone they test and voltage regulator is bad, I order new ac Delco alternator change it.again no crank no start...I clean up grounds, nothing *""'::::;!!!;!?? Pulling out my hair I finally call tow truck to take to my parents mechanic respected local shop tow driver uses jump box and truck starts right up?? Wtf, my actron + scanner is not enough for what I need to do....I know in my heart it's a ground issue but can't solve it, time to bit the bullet, so they get it in and see the bulldog 200 remote start which was not installed very well (poor install) they remove it and continue to diagnose....they have to bring in another guy 30yrs auto electric exp, from their other shop , they have 4 locations in Chicago area (family owned shop) their "ringer" finds the problem...2 can bus wires broken , PCM ground wire broken inside the casing this is the big black wire from center connector, and bad negative battery cable module, it's an induction ground module...the electrical ringer runs temp ground wires and the truck starts and purrs like a kitten their putting it back together as I write this reply.
Was costly 1000. Plus the cable which I ordered thru AutoZone from GM. 37.99 + tax
shop wanted 126.00 but working with me let me order it, thank God !! Saved 86.00!!
Obviously I love this truck and it is in outstanding condition, 8500 miles on new crate motor. Problem was I bought this truck on a screwed up family deal when I had a good chunk of extra money in hand , the only thing that I haven't done is the trans now 155k on that but I keep up the preventative maintenance on it and it's solid/tight.
Bottom line I was in so far on this truck I couldn't get out , like GM...LOL really crying....I moved back home four years ago to take care of my dad he has Alzheimer's decided to go back to school ,through a bunch of money at this truck with the plan on driving it a few years ,no payment, going to need to get 8-10.my faith in GM is shattered never owned a foreign car in my life always GM, old school Dodge/ Chrysler and a couple Ford's, Chevy man at heart, but all the problems have me seriously thinking about ever spending GM again. So now I've basically got a new truck 14k $ in it that's probably worth 5k at best ...gonna drive it into the ground. Sorry for the long story but without the background most would think me an idiot...did I mention I love this truck.
As a kid growing up in Detroit I built lots of motors/cars so I'm no stranger to wrenching , but all this computer garbage hate it!!
Good luck hopefully this helps
 

Maverick6587

Member
Dec 16, 2018
730
Sterling Heights, Michigan
Just a thought as I'm not 100% sure on how the PCM stores crank/timing.

I agree with @Mooseman . I'm thinking that the PCM stored the old engines crank/timing and the new engine's crank sensor and timing chain are brand new. Maybe the timing stored in the PCM is too far off for the new engine to actually start?

A case relearn cannot be done without the vehicle running but, you could have a dealer or mechanic reprogram the computer.
 
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Mooseman

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Dec 4, 2011
25,262
Ottawa, ON
Like I said in my original post, it should run without a CASE relearn.

You need to go back to the basics as tto why it won't start. The fact that the tow truck's booster was able to start it tells me it's either a battery or electrical issue. There are numerous threads on no crank situations.
 
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Gaffer

Original poster
Member
Jul 20, 2019
16
So Cal
Latest update is bad news. In addition to this forum and running down your recommendations, we subscribed to http://www.alldatadiy.com/. This website is awesome if you aren't familiar with it. Using the electrical diagrams, we chased-down every harness, connector, grounds, etc. We had grounds and voltage where they should be. We still had crank, no start, no spark. We towed it to a shop. They ended up pulling the crank sensor and inspected the crank with a camera and said the teeth were broken.

Not knowing what the teeth looked like, I inspected our old block and crank. I can't see anything that could cause teeth to be broken. Attached is a picture of our old crank. Unless something is missing, I'm guessing that crank sensor sees the notches in the crank. Unless you see differently, I'm going to get an inspection camera and look inside the new block too. Pulling that engine is too big of a deal to not try everything else first.

About the engine, it was a fresh, long-block rebuild from an engine builder. It didn't come with the oil pan, but was otherwise complete. They were very particular about our vin to ensure it was the correct engine for a 2006 Trialblazer (VIN S - I guess the 8th digit being very important). Our 8th digit is an S. Are the crankshafts different between years and perhaps that's the problem?

Thanks,
John
 

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mrrsm

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I hate to Park a Dark Pun here by suggesting that you should " ... 'Cast' a Skeptical Eye..." upon the results and conclusions made during the Crankshaft Inspection... but I can make a few observations that might put their conclusions that the Crankshaft Notches have Cracked or Broken Off in very serious doubt. Much of what follows is here is technical... but well worth pointing out for a level understanding for this theory:

The GM 4.2L LL8 Crankshaft is manufactured using a Nodular Cast Iron Process: which has more of the properties akin to the manufacture and strength held in the making of Steels... rather than that of the remaining (6) flavors that Gray Cast Iron can appear in:

Excerpts from:

https://axibook.com/manufacturing-p...ation-chemical-composition-applications/2019/

NODULARCASTIRON.jpgDUCTILECASTIRON.jpgCHEMICALPROPERTIESOFDUCTILEIRON.jpgPROPERTIESOFDUCTILEIRON.jpgAPPLICATIONSFORDUCTILEIRON.jpg

The reason it is worth stressing just how Strong and Resilient Nodular (Ductile) Iron making up the Crankshaft really is... would be like comparing the possibility that Thor's Hammer Mjölnir when wielded by the God of Thunder Himself... would Shatter or Crack if it was swung as hard as possible against his Pewter Mead Mug. Obviously... THIS is not a likely outcome...whether described as a Norse Fable or happening within the confines of Your Engine at Higher RPM in the REAL World.

The very first thing that would have happened if anything somehow DID get jammed in between the Aluminum Engine Block and the Pair of Cast In Reluctor Balance Wheel Notches of the Nodular Cast Iron Crankshaft inside of a running engine would be the result in the Aluminum Cast Pyramidal Wall Chambers where the "CKP" Crankshaft Position Sensor screws into the Engine Block on the Driver's Side crumbling like Egg Shells against any such intrusion by a robust foreign object.

If there is any substantiated Cracking within such a Tough Material... The damage would have to been the result of an Accidental Dropping of the Crankshaft onto a very hard surface prior to the Re-Assembly Procedures of the Engine Re-Manufacturing process; again, but also a very doubtful event if the job had been done by Professional Engine Mechanic(s).

This looks like something that you should look into yourself using a decent but inexpensive 7-9MM USB Digital Camera Probe capable of using Adjustable Light Features and High Quality Imagery to document what you find in there.

While you are at it ...it will make perfect sense to carefully examine the condition of the "CKP"Sensor S/S Hall-Effect Pick-Up Cylinder that inserts in close proximity to that rotational path of the Notched Reluctor Ring and look for signs of obvious breakage, crushing or impact damage to prove that something went awry in between them while it was still screwed inside of the Engine Block.
 

Gaffer

Original poster
Member
Jul 20, 2019
16
So Cal
Thank you for your response. I will pickup a good inspection camera and take a look. We used all the accessories from the original block including the cam and ckp sensors. During diagnosis, when the meter didn't show the correct voltages, we replaced them with AC Delco ones. Nothing changed, but I will inspect all of it very closely. Thanks again.
 
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Mooseman

Moderator
Dec 4, 2011
25,262
Ottawa, ON
I can't see how those teeth could break. Only thing I can think of is that you got the wrong year block or crank. All were the same from 02-07 with 24x teeth. 08-09 changed to 58x teeth.

This is the 24x (like your old block):
Screenshot - 2019-08-25 , 3_23_27 PM_ver001.png

This is a 58x:

Screenshot - 2019-08-25 , 3_23_27 PM_ver001.pngScreenshot - 2019-08-25 , 3_25_05 PM_ver001.png

If you can, get the inspection camera into your new engine's CKP sensor hole to see the teeth.
 

Gaffer

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Member
Jul 20, 2019
16
So Cal
Bad news - Wrong crankshaft. The teeth look just fine though I didn't rotate the crank to see them all. I didn't see the point when it was painfully obvious it's the wrong one for our car.

I can't imagine I have an easy option, but I'd like to hear from you - pull the engine, swap ECU's, anything? I won't be able to talk to the engine building company until Tuesday.

Thanks,
John

IMG_5977.JPG
 
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mrrsm

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Wow... Unless you provided THEM with the Replacement Crankshaft ...I would have to say that the error during assembly would be THEIRS. However... Let's NOT 'Throw The Baby Out With The Bath Water' just yet... There may be the option of replacing your PCM...and possibly your Engine Harness with the Later Model versions if necessary since ...hopefully...there really is nothing wrong with the Re-Built Engine Internals that should prevent it from running.

There are other Members including @Mooseman and @Kelly@PCMofNC who can better advise you of these PCM-Engine Harness alternatives that might minimize any further 'entanglements'. I am very glad that you conducted your own inspection and did not simply pull the engine outright. In the end... it may all work out with just a little more expense.

There are only a few Late Model Trailblazer-Envoy Engine Harnesses available on eBay as per this list...so if the other more experienced Members with this Engine Swap can Chime In... and advise you... eBay may solve the Engine Harness Problem if that idea turns out to be a "GO":

2008 Chevroilet Trailblazer 4.2L Engine Harness:


2008 Chevrolet Trailblazer 4.2L PCM:

 
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Mooseman

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Dec 4, 2011
25,262
Ottawa, ON
I honestly don't know if it's even possible to get it to work, even if you swap the PCM and harness. @limequat may have some ideas. The PCM has to talk to the BCM too to work and there may be other underlying stuff between them. The wiring between the PCM and the rest is likely different and would involve major rewiring or repinning of connectors.

I suppose it's possible to make it work as a standalone as if you swapped it into something other than a GM truck. Problem with that is the cluster might not work, and possibly other stuff like Stabilitrak that interfaces with the PCM to control throttle.

I would investigate your avenues with the rebuilder. If they are at fault for supplying the wrong engine, then you should be able to get some redress from them even though this will involve another engine removal and install on your part.

Any way you look at it, you're in the suck.

This is the second such incident here of a wrong engine getting installed just like this.
 
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Gaffer

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Jul 20, 2019
16
So Cal
Thanks Mooseman. I'm calling the rebuilder today. If I knew for certain a PCM and harness swap would work, I'd certainly consider it. Given your post, I have no interest in experimenting with the electrical systems. I'll report back when I have something conclusive.
 

Gaffer

Original poster
Member
Jul 20, 2019
16
So Cal
Update: Got the engine pulled. Builder picked it up and brought it back after replacing the crankshaft. Got it installed and have crank, no start, but it seemed like it would try. Maybe it was wishful thinking. Anyway, I cleared all codes, tried again and received a P0366 cam position sensor code.

After the first engine install, we tested the cam sensor and replaced it. This was prior to determining the wrong crankshaft had been installed. I pulled the cam sensor and began probing the wires again to test the sensor and wiring. With the sensor out of the car, I turned the ignition on to test for 12V+. I inadvertently turned it enough and it cranked and the engine fired and ran immediately. I just let it go and it stalled after about 10 seconds. I installed the original sensor, and got crank no start. Unplugged the sensor and it started and ran for about 10 seconds and stalled.

I'm close, but stuck. Ideas?
 

mrrsm

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Take a moment to get a still image off of the PCM OEM Part Number for its relevant Years for Installation (then Google that Number) and Post the results in your next response. Also, do a bit of research on whether or not the 'Engine Builder' replaced the Crankshaft Position Sensor (CKP) for some odd reason during their most recent Crankshaft R&R and try to find out WHICH (CKP) goes with either the (7) Notched flavor in the Early Model Crankshaft... or the Updated version for the (58X) [Correction....24X] Reluctor Ring version on the Later Model GM 4.2L Engines. They could have mixed up BOTH of these components.

They SHOULD have Different OEM Part Numbers. You might have to pull the (CKP) presently dwelling inside of the engine... out of the Block to read the Part Number accurately, but if they DID put the Wrong One back in there... your Due Diligence could save your hours of wasted time chasing your tail. So far... these "Engine Builder" Guys have failed to 'impress' with their obvious lack of knowledge about these system variations. Try eliminating the possibilities of having to deal with "Wrong PCM & Wrong CKP" issues next... and lets see what happens.

One last Question... Do you have either an After-Market Radio or an After-Market Remote Starter presently installed on this SUV?
 
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Mooseman

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Dec 4, 2011
25,262
Ottawa, ON
Check the wiring to the sensor. It is prone to breakage due to its position. Do a continuity test on each wire. Make sure the proper cam sensor was installed. Yours is particular for an 06-07 only (ACDELCO 2133519 ). If he put one in for any other years, it may bugger up the works.
 
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Gaffer

Original poster
Member
Jul 20, 2019
16
So Cal
The engine we bought was a stripped long block - no oil pan, valve cover or any external accessories. We used all the original parts from our original engine. There are no aftermarket parts on this car, radio or otherwise.

The PCM has service # 12597521. One website I checked said it wouldn't fit the car, but Rock Auto Parts said it did. The CKP that was in the original block, I still have it, is 12567712 and Rock Auto shows it being correct for model years 2002 to 2007.

The original crankshaft reluctor is the 24X per Mooseman's post above, and I confirmed the new block had that same crankshaft. I reinstalled both original cam and CKP sensors and nothing changed. I will do a continuity test and test for voltages for both the cam and CKP sensors. I know the CKP produces it's own voltage, so I probably can't test that part.

The wires and connectors look fine but I'll throw a meter on them and see what it says.

After installing the first rebuild, the engine wanted to crank even when in the run position. We replaced the switch with an AC Delco one and it seemed to fix it. After this install, the engine started cranking when we connected the battery. Kid inspected the starter and realized he didn't get the wires just right and they were shorting. He fixed it and it's fine, but I still notice when the ignition switch is in the run position, it is very sensitive to crank. Does that sound like something we have screwed up?

Thanks for your help.
 

mrrsm

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Post # 10 ...The Two Videos covering the weird behavior of 'misaligned gear teeth' might still be relevant. This can be harder to accomplish than it might seem because GM did NOT establish a definite "ZERO" Point Position to refer to. The Ignition Key Tumbler has to be correctly positioned OFF and while doing that several times with the Ignition Switch unplugged and removed from the Steering Column... shine a Bright Flashlight up in there and use a small Mirror to visualize the motions as they are happening. You should be able to see the "rack and pinion' set up and see if anything is cracked or wobbles about.

On rare occasions, a FUBARed Metal Key Tumbler can be the culprit. It might take a bit of Trial and Error to ensure that the Teeth in the New Ignition Switch get manipulated...juuuuust right,.. before the problem subsides. If you look over the Ignition Wire Diagram that covers what @MAY03LT describes in great detail as to how each step cascades to a complete Start-RUN... you can see that anything that cause the hidden contacts to touch each other at the wrong time in the Key Rotation Sequence can make the whole thing go sideways ...and simply not work.

JFTHOI....

Hook up an Analog Fuel Pressure Tester to the Test Schrader Port and observe its behavior when Cranking to Start. Also...Make One Last Pass over EVERY Harness Connector under the Hood...as your Assistant may have over-looked something. I know that like mine is to me... that he is the Very Beat of Your Heart...but now is not the time to take anything for granted.
 
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Gaffer

Original poster
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Jul 20, 2019
16
So Cal
Problem solved. This has been a very expensive learning experience. After exhausting all electrical and obvious-to-me mechanical components, we had it towed to a mechanic who specializes in GM, and I told him the history. He looked through the oil fill opening and said the cam reluctor assembly was wrong for a 2006 (picture attached). When this all began, I didn't know there were different crankshafts, and never thought the same would be true for cam. The engine builder should have known. The engine seems to run fine, but I have no confidence in the build. I hope others can learn from our experience and avoid such pitfalls. I am asking the builder to reimburse me for the expensive repair to get it running, but I haven't heard back and doubt they'll just pony-up and do the right thing. Anyway, thank you for all your help through this repair.
 

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Mooseman

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Dec 4, 2011
25,262
Ottawa, ON
Just for reference, that is actually the cam phaser. There were some different iterations of these phasers with different part numbers.
2002-2004: 19179010
2005: 12569502
2006-2007: 12580314
2008-2009: 12589782

I don't blame you for not trusting this build. Just a bunch of screw ups. However, the phaser for a 2006 seemed to have been the right one and now is one for a 2008-9. Maybe it was just defective?
 
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Gaffer

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Jul 20, 2019
16
So Cal
We got buys with work and haven't reported in a while. I paid a mechanic to install the correct cam phaser. He noted the engine had intermittent low oil pressure, but we drove it home. We connected an oil pressure gauge and it, for a while, showed about 60psi. After several miles, it d dropped to about 35psi. Then when slowing to turn, it dropped to about 10psi, and then when we came to a stop, it dropped to zero. Our external gauge showed constant zero while the dash gauge fluctuated from zero to about 25psi. We connected our gauge to a port by the oil filter, if that matters. Under acceleration, oil pressure is fine.

I'm so close to cutting bait with this mess, but figured I probe the forum to see if it is an oil pump issue or could it be something else or a combo of things. Changing the oil pump looks to be dang near as bad as pulling the engine. What say you?

Thanks,
John
 

mrrsm

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Very sorry about the follow on troubles...

In a Nut-Shell... Nominal Oil Pressures for the GM Atlas 4,5 & 6 Cylinder Engines are:

12 PSI @ 600 RPM (IDLE)
65 PSI @ 3,500 RPM (Half Way to Red Line)

The GM Atlas Engine Timing Chain Cover and TorX Fastener attached Gerotor Oil Pumps only came in Two Flavors:

(1) Early Model 4.2L LL8 Engines were fitted with a Gerotor Pump that sported a SHALLOW, Beveled Entry Port and used a BLUE "O"Ring and like-shaped SHORT Oil Pick Up Insert Tube that was bolted in from the bottom of the Oil Pan in two places. There were enough recorded and confirmed Catastrophic Loss of Oil Pressure Failure Incidents involving the Improper Installation of the BLUE "O" Rings and or Stuck Oil Pressure relief Valve and Springs... Which leads us to (2)...

(2 This 'Failure of Imagination in the Original Design' prompted a Re-Design of the Gerotor Oil Pump Lower Flange and Oil Pick Up Tube that involved having an EXTENDED TUBE SECTION leading DEEPER inside of the Lower Cavity of the New Gerotor Oil Pump. It also involved the use of a FLAT, ORANGE RUBBER IMPREGNATED METAL OIL SEALING GASKET and a Re-Design of the Oil Transfer Cavity on the opposing side of the Newly Designed Front Cover. GM Sells this unit as a Combination of the Front Cover with a New Design of Gerotor Oil Pump for around $140.00 as of 2015-2017.

OLDLEFTNEWRIGHT.jpgOLDESIGNGEROTOROILPUMP.jpgNEWDESIGNGEROTOROILPUMP.jpgOLDSTYLEVSNEWSTYLESEALS.jpg42681914194_3fd6b6dc60_c.jpgOLDSTYLEBLUEORING.jpg

These two sub-systems should NOT be Interchanged ...even if the New Gerotor Oil Pump WILL Bolt up to the Old Style Timing Cover. One of the Artifacts you mentioned that is significant is that your Engine Oil Pressure readings dropped precipitously low...WHEN SLOWING DOWN. This indicates that the Oil Pick Up Tube may have been scavenging air because the weight of the Oil was pushing laterally against the lower Oil Pick Up Tube and causing the "O" Ring to temporarily separate right in between the Oil Pump Pick Up Tube and the Base of the Gerotor Oil Pump.

Take Notice How Flattened Out the Used BLUE "O"Ring Seal looks when compared to how "Plump" the Brand New Old Style BLUE Viton "O" Ring appears? THAT is a Potential Point of Seal Failure. It is VERY important to remember that this location is under an EXTREME VACUUM whenever the Gerotor Gears are turning...so any breaks or cuts in the seal will allow the Open Air in the Lower Crankcase to get Drawn Inside and turn the Gerotor Oil Pump into a useless, cavitating Air Pump... at least momentarily. What happens to the Motor Main Crankshaft and Connecting Rod Bearings within a Minute after that can make the difference between a recoverable situation if the Oil Pressure Rises...and a Lunched Motor.

The second possibility is that the TorX Bolts holding the Gerotor Oil Pump solidly to the Inner face of the Timing Cover-Oil Chamber have come loose. I have personal experience with discovering loose TorX bolts on a 2004 GM Atlas 4.2L Engine Gerotor Oil Pump during Post Engine Tear Down...so I know that this actually can happen.

While GM does make the aforementioned New Front Timing Cover - Gerotor Oil Pump Combo... Only MELLING makes the Later Model, Newer Design of the Oil Pick Up Tube with the Orange Gerotor Flange Grommet to match up with it.
 
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TollKeeper

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Dec 3, 2011
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Brighton, CO
So basically, he has to drop his oil pan, to pull the oil pick up tube, and compare what he has to the pictures above to see which version he needs?

And with the block having the wrong crank in it, plus the wrong cam phaser, its likely it will also have the wrong pick up tube/O-Ring/gasket too.

Did you ever get anywhere with the builder refunding your money on the cam phaser?
 
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mrrsm

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If the OP does as you suggest... he will need either One or the Other choices from these items:

For the Old Style Gerotor Oil Pump & Pick Up Tube:

(1) A Brand New GM OEM "BLUE" Viton "O"Ring:

GMOLDSTYLEBLUEORING2.jpgGMOLDSTYLEBLUEORING.jpg43350779592_1324cba187_c.jpg

For the New Style Gerotor Oil Pump:

(1) Melling Part # 358S Kit New Style Oil Pump Pick Up Tube.

MELLINGNEWSTYLEOILPICKUPTUBE.jpgMELLINGNEWSTYLEOILPICKUPTUBE1.jpg

(2) New Orange Rubber OPPUT Sealing Grommet. (Included with Melling 358S Kit)

42681914194_3fd6b6dc60_c.jpg

If this is the decided upon repair path... BOTH of these choices eliminate the need to R&R the Front Timing Cover in addition to the Crank-Case Oil Pan to replace either style of the attached Gerotor Oil Pump(s).
 
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Gaffer

Original poster
Member
Jul 20, 2019
16
So Cal
Thanks guys. We're still debating what to do. The builder reimbursed us for parts only, and said per the sales contract that we should have returned the engine for them to repair - as if it's no big deal pulling it and getting it to them. I'm not going to burn them on line - yet. I have been researching them to consider small claims action. I know without a doubt I'd win a judgment, but collecting is another matter. They have a great and professional website, but their operation is nothing like it. I'm even having trouble locating a business license for them. They do advertise nationwide.

Pulling the pan and front cover is going to be significant although we are pretty good at it now. i really appreciate the feedback and detailed explanation of the oiling system.

Thank you, and I'll let you know what we decide.
 

Mooseman

Moderator
Dec 4, 2011
25,262
Ottawa, ON
I think you'd have a solid case. They screwed up the original build, used wrong parts, and now it looks like the oil pump or pressure regulator is bad or the wrong seal was used on the pickup tube to oil pump.

This has been dragging on since July! You might even be entitled to punitive damages due to loss of time and use of the vehicle. I'd go for the entire cost of the engine.
 

TJBaker57

Member
Aug 16, 2015
2,897
Colorado
Re-reading the thread I see you bought a stripped long block (post #26 above) without oil pan. Was the oil pickup installed by the builder or was it one of the "accessories" swapped over? I've never bought a rebuilt motor so not clear on just what comes with vs what is swapped?

Also I don't know if the pickup is removable without also having to take off the front cover. So it might not even be possible for the pickup tube to have been no already installed by the builder.
 

Mooseman

Moderator
Dec 4, 2011
25,262
Ottawa, ON
Also I don't know if the pickup is removable without also having to take off the front cover. So it might not even be possible for the pickup tube to have been no already installed by the builder.

You must remove the oil pan to remove the pickup and/or oil pump. So in other words, the oil pump and pickup could have been pre-installed by the builder without the oil pan. If they were installed by @Gaffer , that could be their defense.
 

mrrsm

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Oct 22, 2015
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Yes. The Front Timing Cover with Installed Gerotor Oil Pump CAN be Installed...and the person installing the Oil Pick Up Tube later on would be responsible for the Choice of Which Oil Pump Pick Up Tube and whether to use the "BLUE" "O"Ring ...or the Updated Orange-Metal Grommet Oil Seal. The last possibility is that an OLD Oil Pump Seal was used and perhaps invited this problem.
 
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TJBaker57

Member
Aug 16, 2015
2,897
Colorado
I have my own reasons for asking these questions.... My own 2002 4.2 is high mileage and exhibiting symptoms of a bad pickup tube seal that I may choose to address at some point. Mine is a second vehicle so not an urgent need.
 
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