P0014, P0340, and I did the chain, and all the guides

Steevo

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Oct 7, 2012
194
So I had that P0014 code since I bought the car with 108k on it.
Now it has 230K on it. I changed all the stuff related, the Cam position sensor, couple times, changed the VVT, I have a box of those, by the way.
Nothing ever changed. The SES light would go away for a few months, then come back.

So last month I had a guy pull the front off the engine. Changed the chain, guides, whole bunch of stuff. Cost a fair amount, took some time.
Got it back.
A month later, I have P0014s and eventually P0340s.

I bought a thing called BlueDriver, which I do recommend. It has live data from the ODB2.
The cylinder one advance while driving can range from -2 to 48 degrees. Maybe even farther.
So what would cause this? I changed the VVT sprocket, and everything associated with it. All new GM parts. Well, Cloyes chain kit, I think.

The problem is there all the time now, I clear the codes and in a couple hours they are back.

One thing the guy pointed out, the connectors to all the sensors are not really very tight.

Can anyone give any ideas? Does anyone have experience changing those connector pins, and maybe even some of the housings? I wish I could figure out how to order those.
 

Mooseman

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Dec 4, 2011
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The P0340 is throwing a clue right there. Something is wrong with the cam sensor circuit, either the sensor itself or the wiring from it to the PCM. If you have a box full of these, maybe try swapping it. Then, you would need to do a continuity check of its wiring to the PCM. Grab the manuals (link on my signature) for the schematics.

Also, was a CASE relearn done after all that work?
 
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Steevo

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Oct 7, 2012
194
A CASE relearn was performed.
I think the problem is wiring. I am going to try to identify the housings and pins and change some, examine the wiring.
As you recall this car said low oil pressure at one point. I changed the switch, but when the wires were pulled one day it said low oil pressure, when the wires were jiggled it didn't. It's started that again the last week. It's not real, it's wiring.
I have a box of VVT solenoids. Not the sensors, but I have had at least two or three of those in the last year. Grasping at straws.
 

Steevo

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Oct 7, 2012
194
I bought a OBD2 tool called a Bluedriver. Which I do recommend.
It shows the timing bouncing all over. In the live data.
I don't know if that's normal or not. Has anyone seen live timing data from that engine?
 

Sparky

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Dec 4, 2011
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It shouldn't be bouncing around, no.
 

mrrsm

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UPDATE:

This offer from CARid.com is THE ACDelco OEM Replacement Connector and Wire Pigtail for the CPAS (Camshaft Position Actuator Solenoid). Other OEM Connectors-Pigtail Combos can be found here as well:

https://www.carid.com/acdelco/gm-or...mpn-pt2629.html?singleid=312043596&url=899258

ACDELCOCPASCONNECTOR.jpg



If these are what you're after... Browse around this place for an assortment of GM Weather-Pack Connectors with Pigtails:

https://www.wiringproducts.com/general-motors-engine-connectors


Take a look at this as a specific example of what they offer as a Generic GM CPS Connector and Pigtail and compare it against the Old in-dwelling CPS Connector and short length of harness wire in your Envoy. These must be properly soldered in ...with the right sized Auto Quality Shrink Tube Insulators slid onto the three wire lengths B4 you start. Only Cut and Perform Soldering-Shrink Tube Work on One Matched Up Wire at a Time.

https://www.wiringproducts.com/gm-camshaft-sensor-connector-pigtail-1-pc.html


2813f.jpg
Attach files
 
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Steevo

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Oct 7, 2012
194
I don't think that is correct for my vehicle. I have the black connector with a separate gray lock that you pull out, the one that usually gets broken. But I will check more closely.
 

mrrsm

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You have not specified any individual connector by name... but if you are referring to the CPAS (or VVT Solenoid Connector, if you will...) See the updated information I just refreshed in my last post.
 
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Steevo

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Oct 7, 2012
194
That one looks more correct. I am looking for the CPAS, VVT and Oil Pressure switch. But I have seen those connectors disassembled, there are pins that can be crimped, then inserted into those housings. That is more what I would like to find. I can crimp the pins. And I do want to inspect the wiring because that is where the problem may be if not in the pins.
I'd rather avoid buying any expensive pigtails. Too much trouble.
 

mrrsm

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I'm not sure what you mean about "Crimping The Pins"... but if you are choosing to use THAT method over investing in the OEM Connector-Pigtails and a Small Soldering Kit with Auto Electrical Shrink tubing as the means to make these Connector Repairs... Don't kid yourself... you're looking for trouble. Like "PORSCHE"... when it comes to making wires that have been cut...solid state again... "There is NO Substitute..." for REAL Soldered Connections.

Nonetheless... You still seem to be lucky in your request to find the correct R&R Sensors as the ONLY CPAS worth getting when replacing the GM ACDelco or Delphi Part...is THIS one:

Genuine GM ACDelco CPAS from Amazon:

https://www.amazon.com/dp/B00F676LQ4/?tag=gmtnation-20

and for the CPS (Camshaft Position Sensor) this one will do:

https://www.amazon.com/dp/B0791B8GZK/?tag=gmtnation-20

Last but not least... The GM ACDelco Oil Pressure Switch you want is here:
https://www.amazon.com/dp/B0016HURFO/?tag=gmtnation-20
 
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mrrsm

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About Post #7...

"How can I find the P/N for the connectors on the harness?"

The real puzzle here is why you bothered asking the question about wanting the Connector Part Numbers if you never had any intentions of using any and look so askance at having received answers to all of your questions. There is no mystery or talent involved in locating the things I found and pointed you towards... I just asked my (your) Questions using the Search Engine called DuckDuckGo instead of using Google... and I asked the questions as though I were standing in front of a Counterman in any Auto Parts Store and included the following Key Words:

Trailblazer, Envoy CPAS, Connector, Pigtail, Harness..etc...etc...

...and with a little diligence... I managed to find these ...and you could have just as well. So if you find yourself stumped about any "Special Part Numbers'... skip all that nonsense and search the Net in the same way you would have a conversation with that Counterman using common sense, logic and by simply describing the exact thing you want with enough unique details. One last thought... You should never forget to say "Thanks" to him when he finds for you... what you have not been able to find on your own... after spending his own time and efforts on your behalf when doing so... even if you never really wanted the information in the first place. Capeche?
 
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Steevo

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Oct 7, 2012
194
Yeah, I have all those AC Delco parts, and none of them have solved the codes on this vehicle. In the years I've had it they might go away for six months or a year, then back. Replacing the CPAS and the VVT actuator solenoid have only made things change sometimes, for a week or a month or even a year, but then back. The problem is in the wiring or the connectors. I've been grasping at straws. It's not those sensors or actuator. The codes are back full time now. Some harness or connector problem.

When I picked up the car from the timing chain job, changed the VVT too with a AC Delco part from Amazon, the guy who worked on it took the connector apart, the CPAS connector.

He had the pins (crimped, not soldered by GM) in his hand and he tried to bend them so they tightened up with a dental pick. He's an old GM computer specialist. He's worked on car computers since the beginning. I've done the same thing in a pinch. Over the years.

Yesterday I looked at the VVT connector and as far as I can tell it doesn't come apart like the one he had apart, housings off, pins in his hand right before me. I haven't looked at the one he fooled with but I called him and he said "It didn't seem to get tighter when I did that."

So it's not a matter of soldering, I am an engineer and I have all the soldering equipment in the world. I have most of the aerospace crimpers having done avionics harnesses for aircraft for years and years. It would shock me if I don't have the specific crimper for those pins. All mil spec. They had to pass inspection.

Anyway, I appreciate your help. I come here because this is where the smart guys are, who get into this way deeper than I do at my old age. I have my limitations now.
 

mrrsm

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No Sweat Steve,,, We Love Ya Man...It's just a little frustrating when things suggested to ease the pain get side-stepped along the way. @Mooseman 's original admonition about the P0340 being the Clue That Hits the Nail on the Head as far as really dealing with what the actual source of the problem is... The CPAS (and/or CPS) Connectors that was FUBARed by the GM Tech who Gerry-Rigged it when the Engine Repairs were last done. Did he Damage, Stretch or Break any of of the Two ( or Three Wires) in the Connectors when he was fiddling around with them? Listen to Drew's suggestion on how to test that circuit. @Mooseman 's ideas invariably prove that He IS the Smartest Guy in the Room.

But not to worry... Drew... AKA @MAY03LT has created a Youtube Site that focuses not only on How to Change Parts as Needed... but he delves much deeper into the Most Important Part: How to TROUBLESHOOT so many problems with the Vortec 4200 I-6 LL8 Engine Platform. Perhaps he can get you out of "P0340 Purgatory" with the information he covers in this investigation of the very same problem. By the way... as far as Old Age is concerned... If we run a race for Pink Slips... I've got you Beat by Three Codger Lengths for which one of us REALLY is... OTD (Older Than Dirt) :>)


...and here is some more information that better shows the Hall Effect Square Wave Pulse Width Modulation Harness Wire Test on the Scope Screen to back up Drew's observations in the first video. The best way to diagnose the harness dynamically is find the best locations near the back side of the Connector Pin-Wire Inserts with the Purple Cover popped off and insert the Probe Pins and connect the Alligator Clips right there:

 
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Steevo

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Member
Oct 7, 2012
194
I was driving across the desert yesterday, when things digressed. The engine made a funny noise, and then the engine speed went to 5,000 on the tach, and I cancelled the cruise control. Wouldn't run anymore. I think something broke.
So I was towed and here I am without a car at the moment.
Same P0014 code, plus the P1345. Same area of problem, but that may or may not be the cause of the breakdown.
Depending on what is found when this is diagnosed I may not fix it, and I will be off this platform. Oh well.
 

mrrsm

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To be clear about one last thing to consider... if the "Mechanic" who recently performed the work accidentally broke off the internal Stop Tab inside of the Cam Phaser during the necessary R&R... it is possible that it has become locked in one position. If this is the case... the CPS is designated to sense the ACTUAL position of the Exhaust Camshaft versus the VARIABLE Helical internal portion that the CPAS infinitely adjusts via increasing and decreasing amount of Oil Pressure. If the Cam Phaser is Locked Solid in such a manner... the PCM will NOT be able to set and coordinate the proper Spark Timing and Variable Advance and Retard sufficient to keep the engine running right at varied RPM.

And of course this leads us right back to "...the guy..." ( ASE GM Mechanic?) who ostensibly did that repair on pulling the Front Timing Cover and R&Rd the Timing Chain Set, etc. If you have had the Vehicle towed back to his shop... Here are some Questions to ask him when you can make direct eye contact and observe his body language as he responds to these:

(1) Have you ever repaired one of these GM Vehicles with the 4,2L Engines before? ... and when you had the Timing Cover Off... Did you use a Brand New TTY Bolt on the Camshaft Phaser or re-use the Old One?...and where is that mentioned on my Itemized Service and Repair Bill?

(2) Did you perform an Oil Change and Engine Flush prior to beginning the Engine Repair? With 230,000 Miles on the SUV... Was the top of the engine all sludged up?

(3) The Camshaft Phaser is supposed to be pre-set at the factory for the 25 Degrees of actuation movement... is it possible that you broke off the Internal Stop when you tightened up the TTY Bolt? The persistence of the P0014 and the P1345 Codes might be occurring because the Cam Phaser is stuck in one position now.

(4) Did you replace ALL of the Timing Chain Set components when you did the work to include the Timing Chain, Chain Guides, AND the Timing Chain Tensioner as well? What Brand of Kit did you install ...OEM? Cloyes? After-Market eBay?

Hopefully... he had provided you with a Warranty for Parts and Labor once he handed the Vehicle over to you... and will be responsive to this failure that points its Gnarly Finger of Responsibility... right back... at him.
 

Steevo

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Oct 7, 2012
194
Yeah, it was a cloyes set. He is an old gm guy ASE, very experienced. He's worked on lots of these. But I am currently in another state, so there is some doubt whether he will ever see that vehicle again.
And yeah, pan came off, everything was flushed, but I have been doing that every oil change since I had the car. The VVT was brand new, AC Delco that I bought on amazon. It's getting to the point of diminishing returns with this vehicle. I have a guy who is going to look at it. here and see what's what, but not sure when.
 

Steevo

Original poster
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Oct 7, 2012
194
I ended up having that vehicle sent back to the guy in CA who worked on it. There was nothing else I could do.
He took it all apart again, and declared the Dorman VVT to be defective and the cause of the problem. He then complained to me that I had shown him one on Amazon Warehouse Deals at a cheap price, which he ordered and used. I said all same brand parts are the same, and it had clearly never been installed. We wouldn't have used it if it had been installed at all.
Please hold any complaints about that being a Dorman not AC Delco part!

So after it was all back together, he started it yesterday and it has a knock. Checked the oil pressure with a gauge, 15#. So that's the problem. That would be why the VVT is not working, not enough pressure. That oil pump was not replaced but during the timing chain repair all the front was off the engine. Everything was examined and cleaned including the dip tube and pan. I suggested that there could be a piece of plastic guide in the pump inlet but he says no. I am in AZ, he is in CA.

So now he declares the engine to have a rod and mail bearing problem. Spun bearing.
Well, hell.
I am thinking that this is just too much trouble for this vehicle and too much money to spend on it. We found some supposedly working engines for $500 or even less at wrecking yards. Might be too much to get and put it in. If I hadn't done the transmission and paid for a lifetime warranty I wouldn't consider it at all.

Do these oil pumps fail, much?
 

mrrsm

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They do if the Oil Pick Up Tube gets so Lacquered Up (Think Gooey Licorice here...) and Gunked to the point of being unable to allow Motor Oil to pass through the small screen-covered opening down in the bottom of the Crankcase. The other problem is located at the OTHER end of the Oil Pick Up Tube where some of the Early Model Gerotor Oil Pumps had nicks and cuts in the Blue "O" Ring that would flatten the ring and fail and allow Air Cavitation to occur and prevent adequate suction between the Oil Pick Up Screen Intake and the Short Aluminum Insert Tube interfacing the bottom of the Gerotor Oil Pump at the base of the Engine Block.

The result in both cases is is that an insufficient amount of incoming Motor Oil necessary to keep the Oil Pump Primed and projecting oil under pressure at a minimum of 12 PSI and a maximum of 65 PSI will spell the Death of the Engine from Oil Starvation ---> Leading to Friction---> Leading to Serious Engine Wear and Seized Engine Bearings---> Leading to Catastrophic Engine Failure. It is very likely that if the Oil Pick Up Tube was cleaned during the First Repair Efforts... the damage necessary to cause the bearing to seize upon the Crankshaft Journal(s) was already done.

If your 'California Dreamin' mechanic says that you have a "Spun Bearing"... you will need to take that engine apart...right down to the block in order to get the Crankshaft Bore---> Align Bored... so in much the same comparison as him finding a Dead Whale on the Beach.... there is only so many things you will be able to do with that engine from here on out. It is doubtful that you will find a decent GM 4.2L Engine for $500.00 ...especially in The State of California. Right now there are contemporary posts in the upper right side of the screen on this very same topic that you should take the time to read and consider the wisdom there before you proceed further.
 
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Steevo

Original poster
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Oct 7, 2012
194
I don't see that vehicle being at all worth disassembly of the engine to that level. Maybe another engine, but even that seems doubtful.
I'm not at all sure there is a spun bearing, but there is clearly a lack of oil pressure at this moment.
There was no sign of that problem, and the vehicle has not been run in that condition. Not driven for sure. It's normally quite obvious when there is low oil pressure, you can hear it. Never happened when driving, or even when the vehicle was in service.
 

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