Intermittent p0014 after engine swap in 02 trailblazer?

jimbrown87

Original poster
Member
Mar 2, 2014
17
Hey guys! I recently, 2500 miles give or take, had my 4.2l i6 swapped out after a piston completely disintegrated on my way to work one night... it was bad and I have a pic to share1541.jpeg . I worked with my mechanic and got a great price on a remanufactured engine and the install, including doing some grunt work myself. When I got the truck back, my guy said it had the p0014 after the swap so they switched out the sensor behind the PS pump (cpas?), no luck. Changed the sensor on the front of the engine (can't recall the name off hand) no luck. Told me to drive it, change oil religiously for a while and see what happens. I scanned it with my bluetooth scanner and the torque app and got a pending p0014, after a while I changed the oil and the code became intermittent. Now it will be pending for a few days, then disappear again for a few dive cycles only to pop up again. My mechances said it may need a new pcm? I feel I may need the cam position sensor(?) relearn with a tech2, I've heard it must be done when the sensor is changed. Should I clean the screens on the cpas,even though it and the engine are new? Could breaking in the engine clog the screens, I just don't know. I don't have a clue where to begin as time and money are sparse at the moment. The car runs like new, and after new shocks front and rear and new tires and brakes/rotors it rides smooth too. Also, thanks to info from this site, my 4wd is working flawlessly so my new discoverer at/3's might actually see some dirt and mud lol this go round. Any advice is much appreciated! Thanks in advance!
 

mrrsm

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The answer to the question about having the CPAS Screens clog up after having been cleaned already is ...Yes. Motors that have been dormant sitting in junk yards at the worst and at best ...on LQK-like shelves for a very long time...long enough that when the engine is finally started.. the Oil By-Pass Valve just above the Oil Filter Manifold can briefly open and allow dirt and detritus to slip by and wind up immediately getting trapped in the CPAS Screens...which is within 18" of the incoming start of the Oil Flow,,, causing the screens to get clogged with Congealed, Old Oil and Dirt that have been sitting in the vertical oil gallery since the engine was last operational.

These Questions can help get things going in the right direction:

(1) Was it necessary for the Mechanic(s) involved in the Swap to do any work internally on the Motor... such as pulling the Timing Cover to replace any of the Timing Chain Components?

(2) When the Swap was made... did the Original PCM follow the Re-Manned Engine into the Truck?

(3) Do you still have the Oil Filter(s) that came off of the Engine available for an 'Autopsy'...?

(4) Was this engine truly a completely Re-Manufactured one or taken from another Vehicle as is?

(5) Did the Mechanic(s) give you a list of everything they either took off...put on...or changed in any way working on this Motor?

(6) When you Changed the Oil in this Motor several times... did you also change out the Oil Filters as well on each and every occasion? When servicing the CPAS for either cleaning or replacement... changing the Oil and Oil Filter is part and parcel to the fix.

(7) Can you shoot a few "Walk-Around Videos to serve as a Baseline for the Members to listen to the Engine... From Top to Bottom...and from the sides and underneath the Truck… as well as holding the Camera over the Oil Filler Neck with the Cap Off when the Engine is at Idle? You'd be surprised how Good the Guys are around here for picking up on the subtle sounds of things that may not be quite right… sooner than later.

(8) Do you have a complete list of PXXX Codes that include others besides the P0014?

(9) Do you still have the Original “Piston-FUBARed” Engine around for “training purposes” here? From a ’preventive medicine-maintenance’ perspective… many of our Members would be very curious to know much more about what that Defunct Motor looks like… inside and out; especially in the areas affected by the self-destructed “Plug”. So when time permits ...any volunteered images with a related story about how it all went down in a separate post would add to our collective understanding of this rare occurrence.
 
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Tiggerr

Member
Jun 6, 2013
1,324
Perrysburg, OH
What was the brand of the CPAS installed? If it's not an AC Delco OR GM/Delphi part it could be no good. These trucks seem to only like OE parts for sensors and things like that.
It's well known that the CPAS is especially picky
 
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jimbrown87

Original poster
Member
Mar 2, 2014
17
This is a reman engine,the mechanic didn't mention anything about any internal work on the new engine. I did get a complete list of parts he changed, not sure of the brands though. The pcm in my truck is original to my 02, no pcm with the "new" engine. I do not have the old engine, I wish I did! My mechanic was mindblown by the damage.I always change the filter and oil at the same time, I may still have the first fliter in my "dump pile" I will have to check and disect it if so. I will be cleaning the cpas today since weather is nice, I will be sure to snap some pics/video when my hands are clean enough...no assistance lol. Thanks for the help guys, I will update tonight or tomorrow. I will also get in touch with my guy and see if he has anymore info on what exactly went wrong with the old engine. Thanks again guys!

Also, the vehicle hasn't thrown any other codes since I've had it back. P0014 intermittently is all I have seen, and all the mechanic mentioned. I will be sure to shoot the video you asked for, just to have you all give your opinion. I appreciate it!

I got out the list and minus the reman engine he replaced the intake manifold (filled with metal bits)plugs,tensioner, 4x4 housing, cam sensor, crank sensor and probably most important is the timing solenoid. I don't know if the timing would have been effected when changing the solenoid, but he never mentioned opening up the new engine. Video coming soon.
 
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jimbrown87

Original poster
Member
Mar 2, 2014
17
Hopefully I got what is needed in this vid,I'm no cinematographer lol. I hear a slight ticking under the front drivers wheel well,hopefully that translates to the vid. Like I said, the car runs like a Ichamp since the swap but this code is driving me up the wall lol! I'm having trouble uploading the video here so here is a youtube link...
Let me know if I missed anything, or totally screwed up the vid lol.
 

jimbrown87

Original poster
Member
Mar 2, 2014
17
As for the old engine, it had 212,000 miles and was starting to have problems. The power steering pulley fell off and the engine overheated. Then the water pump failed and by the time it arrived at the mechanic it was blown. He was so amazed at the damage that he sent me that pic of the piston. He said when he got there that morning he started it right up, it had a terrible sound so he shut it down and told me it was blown. He said it ran with that piston like that until he shut the key off...pretty dang tough in my opinion I got the truck for a steal and I love it so I decided to keep her and put in the new engine. I was very maintenance minded the whole time I've owned the vehicle, I can't speak for the previous owners though...
 

Mooseman

Moderator
Dec 4, 2011
25,392
Ottawa, ON
You absolutely need what's known as a CASE relearn (aka: Crankshaft Angle Sensor Error relearn). It has to be done either by a dealer or a shop with a Tech 2 or a very high end scanner. The PCM still has the settings from the old engine.
 

jimbrown87

Original poster
Member
Mar 2, 2014
17
You absolutely need what's known as a CASE relearn (aka: Crankshaft Angle Sensor Error relearn). It has to be done either by a dealer or a shop with a Tech 2 or a very high end scanner. The PCM still has the settings from the old engine.
That was my first guess, but it seemed weird it would be intermittent if that was the case. I don't know if my guy has a tech2 or equivalent,but I guess I'll be looking for a local shop with one... my local gm service/dealer is a crook! I appreciate the info sir! I will update as to whether this is the fix or not, once I get er done lol.
 
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jimbrown87

Original poster
Member
Mar 2, 2014
17
Just an update, still haven't located a shop able to perform the CASE relearn. I have burned the bridge,so to speak, with my local dealer over some problems we had in the past. I will keep looking. The p0014 code is still intermittent,but the CEL seems to be off more than on since I made the original post surprisingly. I didn't get any feedback on my video, I probably didn't film it right for you guys I bet lol. I've heard tales of a "manual" CASE relearn by going through a set of driving techniques, cruising at certain speeds for certain lengths of time, sounds alot like the procedure to get your vehicle ready for inspection. If anybody knows if there is in any truth to the manual case relearn procedure, I'd be ecstatic to hear so!I appreciate the help, and will update again once I figure this out.
 

mrrsm

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Oct 22, 2015
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Jim... Your Video Shoot is just about as good as it can get... but if things develop with that "ticking" sound and you can shoot a bit more from underneath the vehicle while the SUV is up on Ramps, Emergency Brake Set, Wheels Chocked... it would provide more information. Getting a Used Engine is like a Pot Luck Dinner... You just never know whats under the "Lid".

Right now... there is a contemporary thread (among many others) that would help you get more information about the PXXX Code issues and give you some other insights into how to investigate the problem... especially on the last few messages here:

http://gmtnation.com/forums/threads/my-cursed-engine-rebuild.16785/

One way or another... without having a Base Line CASE Re-Learn done... you won't know where to go from here. There are No Manual Ways to perform a CASE Re-Learn... and anybody claiming they have "A Method" is just pulling your chain.
 
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shovenose

Member
Apr 24, 2016
318
SF Bay Area, CA
Honestly the engine sounds acceptable. Was it an actual name brand remanufactured engine or just a used/junkyard engine? From what I've read on here a CASE relearn is absolutely needed and it should solve your problem.
 
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Mooseman

Moderator
Dec 4, 2011
25,392
Ottawa, ON
All the CASE relearn does is give the PCM a baseline to report any camshaft/crankshaft angle variations, for example, if the chain stretches or tensioner breaks. You can run it until it's done without worry but may affect drivability a tad. All the times I needed a CASE relearn, I was able to drive it until done.
 
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jimbrown87

Original poster
Member
Mar 2, 2014
17
Thanks for the info guys! I'm widening my search area for a shop with a Tech 2 or equivalent. I'm pretty far out in the sticks here lol! Every shop I've called has either no clue what I'm asking for, or they just refer me to my local dealer. I may end up forcing myself back to the dealer, but I'd drive an hour out of my way to avoid it. The engine is not used from a junkyard, my mechanic ordered it from his parts guy to the tune of $3200 If I remember correctly. Everything feels like new when I'm driving, but I will definitely keep my eye/ear on that ticking. Mooseman, when you say I can drive it until it's done, do you mean I can drive it until the pcm actually relearn itself, or that I should be able to drive this thing until the wheels fall off with no major issues other than the CEL? Thanks again fellas, I will be sure to keep this post updated.
 

Mooseman

Moderator
Dec 4, 2011
25,392
Ottawa, ON
You can drive it with no ill effects except for the CEL.
 
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jimbrown87

Original poster
Member
Mar 2, 2014
17
Update.
I asked my guy about the case relearn and he said he performed it,and it was successful. He used a Matco Maximus 2.0 scanner. We both wondered if this scanner is capable of performing the relearn required for this vehicle or if it would be some other specific model scanner. The only 2 I know for sure are the Tech 2 and the snap on mt2500. If anybody knows if his matco maximus 2.0 is capable of performing the proper procedure I'd appreciate it.
 

mrrsm

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Oct 22, 2015
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If you get the opportunity... ask your mechanic (unless you yourself saw the engine while is was still strapped inside the crate prior to the installation happening) and ask him these questions.

"Did the Motor come with the Harmonic Balancer already installed?"
"If not... Did you install the Harmonic Balancer off of my old FUBAR'd Engine?"
"If you installed the Old HB... Did you also use the Original HB Crankshaft Bolt?"
"If you installed the Old HB using the Old Crank Bolt... How did you manage to do that?"

As you question him... Please ,,, Note any delays or pauses in his responses.... watch the look on his face and observe his gestures for anything sketchy that might cause you to doubt the honesty of his responses. There is no Sin in not knowing something as arcane and unusual and yet so very necessary about this Strange Power Plant… but not being honest about it will hold great import for you over time as to how and why this problem must be rectified ASAP before the engine begins to accumulate many more miles:

The reasons for this question have to do with the fact that whenever the GM 4.2L LL8 Engine is fitted with a Harmonic Balancer… its success for being held rigidly and firmly in place without loosening up over time and wreaking Havoc on the Rotating Assembly is wholly dependent upon the following factors; without which solving the questions about either P0014 or P1345 Codes, or both… ultimately will become an impossibility.

(1) Whenever a Harmonic Balancer is installed, a Brand New Crankshaft Bolt is required. This fastener is first tightened down with 110 Ft Lbs of torque… while the Crankshaft position is fixed and held fast at the Flywheel… NOT while using any means to hold the Harmonic Balancer in place as it will NOT stop the Crankshaft from turning and the proper amount of tightening force will NOT be achieved.

(2) After the application of 110 Ft Lbs of initial force… a White Enamel Paint Line is drawn vertically down along the Timing Chain Cover...straight down over the face of the Crankshaft Bolt and finishes on the Timing Chain Cover at the bottom. This allows for an additional 180 Degrees of Torque Angle to be applied clockwise until the line covering the face of the Crankshaft Bolt is once again...straight up and down and in line with the two white paint marks on the Timing Chain Cover.

(3) As long as the rectangular slot inside Lower Crankshaft Timing Chain Sprocket has not been damaged and the Crankshaft Pin inserted into the nose of the Crank is new and undamaged… once the proper tightening sequence is achieved as described in (1) and (2)… the P0014 and P1345 Codes should clear and not reappear … unless the Old CPAS sensor was installed and was dirty before it was put into the Newly Re-manufactured Engine.

I know…. It all sounds so very mysterious…. But without following these instructions with precision and care… there no way to prevent the Harmonic Balancer from loosening even further and making normal operating conditions without excessive engine vibrations and without misfires and without poor performance happening again and again.

The Fix for this does NOT require him to do anything more extravagant than removing the Used Crankshaft Bolt… and securing the Flywheel with two pairs of Vice Grips grabbing hold of the outer Ring Gear right adjacent the Bell Housing to resist all movement. And then performing the Crankshaft Bolt Tightening Sequence exactly as described in (1) and (2) listed above…. And all while using a Brand New Crankshaft Bolt (about Ten Bucks at any GM Dealership or via gmpartsdirect.com) and with a White Enamel Paint Pen to make the alignment line. After that… Clear the Codes… Start the Engine for a Warm Up… and take it for a short Test Drive…. No Codes? Yer Done!
 
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jimbrown87

Original poster
Member
Mar 2, 2014
17
I will inquire, I saw the engine wrapped in the crate briefly while checking progress. Not sure about the harmonic balancer. The job sounds like something I may be able to do myself, unless I am overy confident. He replaced both the sensors trying to rectify the situation. The one I believe is the cpas (must move PS pump to remove) I cleaned today following instructions on this site, very easy by the way. It was in like new condition, as expected, no screens missing. I cleaned and reinstalled it anyway. I will update once I inquire about the harmonic balancer,hopefully tomorrow,probably Monday. Would there be no way to tell visually if the bolt was old or not? Thanks so much guys for all your continued help!
 

mrrsm

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Oct 22, 2015
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In some cases... TTY Bolts (Torque To Yield) can be measured with an accurate Digital Outside Micrometer to compare with New TTY Bolts for any "un-rebounded" length that would indicate the Plastic Deformation level achieved durig its use has not only reached ... but exceeded. But doing this action at this point would be akin to trying to separate Fly Sh*t from Pepper and in any case... if that Mechanic gives the high sign that he DID re-use the Crankshaft Bolt... that would mean that this "Use Once and THROW IT AWAY" Fastener has been subjected not only to the initial GM factory tightening stresses... but gone through the torture ...Twice.

If the Crankshaft and Harmonic Balancer were slotted and fitted with a proper Woodruff Key... I would say... button it up with the Old Bolt. But that technology does not exist in this case...and the consequences of failure by having the Old Bolt tightened down and give only the appearance of being properly held in place cannot be tolerated by having an enormously massive, Elastomerically glued together, two-piece circular Chunk of Metal that would break all the bones in your foot if you dropped it on it from the height of yard stick... get loose,

Try to imagine that this balancer is trying desperately to separate itself from the horrendously powerful torsional forces being forced into it by the Crankshaft. If this is happening while the loosened Harmonic Balancer is sliding forwards and backwards countless times during periods of acceleration and deceleration right in front of a re-used, pre-stretched fastener at up to 6,500 RPM when it SHOULD be held there with an enormous amount of elastically reactive new metal that can only happen by using a Brand New TTY Crankshaft Bolt to perform this critical job.

That Bolt MUST remain like a Super Strong Rubber-Band for the life of its use in the nose of the Crankshaft inside your Engine. Once it has been stretched and removed... you might look at it and think, "WTF? It looks Okay to me..." Forget about it... it's done. And so it would be a tragedy to find out that this New Engine might not get the same opportunity for a very long service life for the sake of a $10.00 Part. This is not a trivial matter where this engine is concerned. GM has produced documentation that specifies "If the P0014 problem cannot be remedied with the Tech II approach...THEN REPLACE THE ENTIRE ENGINE".

So this is why I stress that you need to get the Absolute Truth out of the Shop Mechanic when you interrogate him about the subject. Trust me... this GM 4.2L Atlas Engine Exchange will probably be the first and last of its kind that he will ever do... and unless he is a Member in Good Standing here at GMT Nation... He will not know any more about these All Aluminum I-6 engine idiosyncrasies than the Average Mechanic does; many of whom can get very "creative" with how they do things when not under the watchful eyes of the customer. So I'll close by saying once again by suggesting that you find out first hand if any of this is true. If you decide to R&R the Bolt... We can all help you get the job done right.
 
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jimbrown87

Original poster
Member
Mar 2, 2014
17
MRRSM, I appreciate that info! I know, and trust my mechanic and have for some time. If anything is the problem, it is that he is just a lil dumb lol. I know he has previous experience with our platform. I met 2 people he has done work for, including an 04 trailblazer he swapped a junkyard motor into. I don't want to discredit your position, like I said if he is unaware of this stuff, I believe he had no clue. Obviously I value what you guys say, I have learned more from this site than I could have ever figured out by myself. That said, I will be having the harmonic balancer discussion with him asap. I even wrote down a version of the exact questions I was told to ask him lol. I'm pretty good at reading people, let's see what he says. I've put enough money in this thing, anything else I can reasonably do myself, I will. I still wonder though, is his matco maximus 2.0 capabe of performing the relearn I need? He said it was done, but even he was unsure if our pcm needed something more specific than his tool can handle. I got out my receipts and don't see mention of a new harmonic balancer, so I'm sure he reused my old one, or the new engine already had one, no mention of the bolt either. Hedidn't hesitate to tell me when I needed to buy new parts, hopefully he didn't skimp on a $10 bolt! The engine came with a 3 year part replacement warranty, and 1 year labor replacement warranty so i guess I'm covered if I got a dud. Hopefully he is around tomorrow...
 

Sparky

Member
Dec 4, 2011
12,927
What is this, a criminal investigation all of a sudden?

Sure, ask the questions because they could be valid and all. But "investigation" and looking for sketchy eye movement...?
blinkhuh.gif
 
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jimbrown87

Original poster
Member
Mar 2, 2014
17
Lol! Nope,no investigation. I plan to find out whether or not he reused the crankshaft bolt or not and I want to ask him in the proper way. If it were ANY other mechanic I've used in the past, it would be an investigation. I know this guy didn't try to lie or screw me, but he may not have known about this particular procedure. He is far from a GM atlas specialist, but he has pulled atleast one trailblazer engine and replaced it with another. More than can be said for most mechanics in my area,not including the local GM service, which I refuse to return to. If he reused the bolt, he will tell me. If he did, he will fix it. I try to do everything I can for myself, but plenty of things are out of my scope (driveway mechanic with a 6 year old helper) lol! He even told me his matco scanner had the option to perform the CASE relearn, but wasn't positive that our vehicles didn't require something else he couldn't perform with his tool. I just want this dang code to go away lol!
 

Mooseman

Moderator
Dec 4, 2011
25,392
Ottawa, ON
If everything checks out and the CASE relearn was done, I wonder if the cam phaser was replaced by the rebuilder?
 
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