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2002 gmc envoy_slt_xl
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Discussion Starter · #1 ·
I've had P0013 & P0014 for years now. Finally decided I didn't want to deal with the rough cold starts and 10mpg gas mileage anymore. Below are the things I've done.
I've read countless threads here, as well as all the videos I could find on Youtube to try to solve this. I'm focused on the P0013 circuit malfunction, as this is likely causing the P0014 over advance condition, as the PCM is not able to control the solenoid/phaser.

VVT solenoid w/ oil change 3 months ago (generic)... no change

Camshaft phaser/timing chain replaced w/ oil change, one week ago... no change. The old phaser was crusted and locked up. It took some working with a pipe wrench to get it free. Once free, the spring tension was very low, so I suspect it had been not working for a very long time and had seized up.

Pulled the VVT and made sure the screens were clean, they were.

Swapped PCM, after a few cycles the codes were back, no change.

I've also probed the VVT solenoid harness pins, +12V on one and ground on the other. I've unplugged the harness from the PCM and checked for a short circuit to ground on the wires, and all was good. I've applied 12V straight from the battery to the solenoid and can hear it clicking just fine.

Here is what I plan to try in the next day or two....

Check the resistance on the VVT solenoid, should be 8-10ohms.

With engine idling, apply direct battery voltage to VVT solenoid. This should stall or stumble the engine, this will tell me that the system would work if it were to get voltage/command from the PCM.

If that tests okay, I will probe the harness, run the wires into the cabin with a spare solenoid and multitester, drive around to see if the PCM is actually sending the signal under normal driving conditions, however I'm wondering if the PCM will not do anything with the VVT circuit after the circuit is checked and the P0013 code is there, might need to clear the codes, then immediately take it for a drive.

Something I thought was strange was that I probed the harness, verified 12V, but the second the harness is plugged into the VVT solenoid, the voltage goes to 0, and the solenoid never clicks. A tech video that I watched showed that this was normal, so must just be how the PCM works with controlling the voltage & pulse, but just seemed strange to me, apparently that is normal.

Can anyone please give me your thoughts? I've spend so much time and $$ on this issue, I feel like I have to get it fixed.
 

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The typical catechism for these codes is what it appears you've already done:
  • Dirty Oil
  • Low engine oil level
  • Faulty Exhaust Camshaft Position Actuator Solenoid Valve Bank 1
  • Exhaust Camshaft Position Actuator Solenoid Valve Bank 1 harness is open or shorted
  • Exhaust Camshaft Position Actuator Solenoid Valve Bank 1 circuit poor electrical connection
  • Faulty Engine Control Module (ECM)
.. so I won't got there for you all over again.

Here's what catches my eye:

"Something I thought was strange was that I probed the harness, verified 12V, but the second the harness is plugged into the VVT solenoid, the voltage goes to 0, and the solenoid never clicks. A tech video that I watched showed that this was normal, so must just be how the PCM works with controlling the voltage & pulse, but just seemed strange to me, apparently that is normal."​

Here's where a cheap logic probe is very valuable. LINK HERE

► That the 12V base goes to 0V when it's plugged into the ECM is all well-n-good - but when it's open, is there any ground potential at the pin that controls the VVT solenoid?​
► Are you using a meter or a test light to confirm the 12V change? I know it's tempting to stick it with a test light - but the meter will tell a lot more.​

THEN the logic probe will also tell the state of the wire at any time the engine is running - ground or power?

Be Ye veri careful with a test light on a computerized circuit! I guess you know that - but I put that in here for if/when this response gets Googled and someone else reads it.

I hope Chem_Man shows up with his library of schematics. Soon!
 

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2004 chevy trailblazer_lt
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Attached are two schematics - one for the ignition (CKP & CMP sensors), and one for various controlled/monitored subsystems.

Hope these help. Let me know if you need any others.
 

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Thanks - don't go too far away ............ just sayin'................
 

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OK. I'm here for quite awhile.
 

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................. well ......... maybe not tonight! It's his move anyway.
 

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2004 chevy trailblazer_lt
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True. I'll be around tomorrow when I am not wrenching. Need to replace the HVAC Mode actuator on our 99 Silverado after I finish my rewiring job on the Buick Century.
 

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I had ordered a set of new rotors - front and rear from Amazon Smile - AKA: Detroit Axle.

The rear rotors were fine but the fronts were about 3/4" too large in diameter.

I'm trying to straighten this out now.

I've never seen SMALLER rotors on the front - have you?
 

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2004 chevy trailblazer_lt
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I've never really noticed.

Last time I replaced rotors was 15 years ago when I redid the brakes, front and rear on the Silverado. Factory brakes wore out in under 24,000 miles. Consensus on the various forums was to replace pads, rotors and calipers. Apparently, GM had a problem with crappy brakes that year on the Silverados and Sierras and even dealerships were advising customers to replace with non GM parts.

Since you mention Detrit Axle, well, they are not on my "Approved to buy from" list. I might have ordered Wagner or Raybestos rotors from Rockauto.com.
 

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2004 Trailblazer LS 4.20 L
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I've had P0013 & P0014 for years now. Finally decided I didn't want to deal with the rough cold starts and 10mpg gas mileage anymore. Below are the things I've done.
I've read countless threads here, as well as all the videos I could find on Youtube to try to solve this. I'm focused on the P0013 circuit malfunction, as this is likely causing the P0014 over advance condition, as the PCM is not able to control the solenoid/phaser.

VVT solenoid w/ oil change 3 months ago (generic)... no change

Camshaft phaser/timing chain replaced w/ oil change, one week ago... no change. The old phaser was crusted and locked up. It took some working with a pipe wrench to get it free. Once free, the spring tension was very low, so I suspect it had been not working for a very long time and had seized up.

Pulled the VVT and made sure the screens were clean, they were.

Swapped PCM, after a few cycles the codes were back, no change.

I've also probed the VVT solenoid harness pins, +12V on one and ground on the other. I've unplugged the harness from the PCM and checked for a short circuit to ground on the wires, and all was good. I've applied 12V straight from the battery to the solenoid and can hear it clicking just fine.

Here is what I plan to try in the next day or two....

Check the resistance on the VVT solenoid, should be 8-10ohms.

With engine idling, apply direct battery voltage to VVT solenoid. This should stall or stumble the engine, this will tell me that the system would work if it were to get voltage/command from the PCM.

If that tests okay, I will probe the harness, run the wires into the cabin with a spare solenoid and multitester, drive around to see if the PCM is actually sending the signal under normal driving conditions, however I'm wondering if the PCM will not do anything with the VVT circuit after the circuit is checked and the P0013 code is there, might need to clear the codes, then immediately take it for a drive.

Something I thought was strange was that I probed the harness, verified 12V, but the second the harness is plugged into the VVT solenoid, the voltage goes to 0, and the solenoid never clicks. A tech video that I watched showed that this was normal, so must just be how the PCM works with controlling the voltage & pulse, but just seemed strange to me, apparently that is normal.

Can anyone please give me your thoughts? I've spend so much time and $$ on this issue, I feel like I have to get it fixed.
have you pulled the vvt solenoid and applied battery voltage to it? supposed to place a pencil in the port and the solenoid should click and push the pencil out about a quarter inch. my next hunch is the one im fairly solid on; ports are clogged and crusty and the oil can't get to the sensors and such. at least not with enough pressure to pass the pcm's tests. im having a similar problem but with p0016 which is suppressed temporarily by oil changes and warm starting. ive been trying to carefully flush out the crud with seafoam. i add a shot or two after oil change, then more soon before changing the oil again as per the recommendations. could be improper connector alignment also. those things can be super picky and the wires sometimes break right there inside the insulation. pita
 

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Oops ...... I just noticed I posted that in a non-private chat! Oh well ... the secret's out.
 

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2002 gmc envoy_slt_xl
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Discussion Starter · #13 ·
The typical catechism for these codes is what it appears you've already done:
  • Dirty Oil
  • Low engine oil level
  • Faulty Exhaust Camshaft Position Actuator Solenoid Valve Bank 1
  • Exhaust Camshaft Position Actuator Solenoid Valve Bank 1 harness is open or shorted
  • Exhaust Camshaft Position Actuator Solenoid Valve Bank 1 circuit poor electrical connection
  • Faulty Engine Control Module (ECM)
.. so I won't got there for you all over again.

Here's what catches my eye:

"Something I thought was strange was that I probed the harness, verified 12V, but the second the harness is plugged into the VVT solenoid, the voltage goes to 0, and the solenoid never clicks. A tech video that I watched showed that this was normal, so must just be how the PCM works with controlling the voltage & pulse, but just seemed strange to me, apparently that is normal."​

Here's where a cheap logic probe is very valuable. LINK HERE

► That the 12V base goes to 0V when it's plugged into the ECM is all well-n-good - but when it's open, is there any ground potential at the pin that controls the VVT solenoid?​
► Are you using a meter or a test light to confirm the 12V change? I know it's tempting to stick it with a test light - but the meter will tell a lot more.​

THEN the logic probe will also tell the state of the wire at any time the engine is running - ground or power?

Be Ye veri careful with a test light on a computerized circuit! I guess you know that - but I put that in here for if/when this response gets Googled and someone else reads it.

I hope Chem_Man shows up with his library of schematics. Soon!
I thought I'd have time last night to mess with it but I didn't, maybe tonight. I'll report back after I do a couple tests. I plan to jump 12v to the solenoid while running and see if the phaser moves, as well as check the ohms on the solenoid. If the phaser functions when jumping the solenoid, I'd maybe suspect that the solenoid resistance may be out of spec, and when the PCM first checks the circuit, it may trip the pending P0013. I do notice after clearing the codes, the P0013 (circuit malfunction) PENDING shows up right away. The circuit looks very simple, just a +12V control, and a ground, I feel like it almost has to be something with the VVT solenoid., but further testing should let me know. Thanks for the info guys.
Also, I'm using a standard multitester, but I may snag one of those test lights, I can see that coming in handy when a multitester is not easily used.
 

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Discussion Starter · #14 ·
have you pulled the vvt solenoid and applied battery voltage to it? supposed to place a pencil in the port and the solenoid should click and push the pencil out about a quarter inch. my next hunch is the one im fairly solid on; ports are clogged and crusty and the oil can't get to the sensors and such. at least not with enough pressure to pass the pcm's tests. im having a similar problem but with p0016 which is suppressed temporarily by oil changes and warm starting. ive been trying to carefully flush out the crud with seafoam. i add a shot or two after oil change, then more soon before changing the oil again as per the recommendations. could be improper connector alignment also. those things can be super picky and the wires sometimes break right there inside the insulation. pita
Yes, when I replaced the phaser and timing chain components a couple weeks ago, I pulled it out and checked, cleaned it out as best as I could. The screens were about 99% clean, and I did apply voltage and heard it click, but did not check for any motion of the solenoid. I'll take a closer look at that and see if it's actually moving. The solenoid is, just a guess, 4-6 months old at this point, but it was not OEM, so could be problems. Yeah, I probed the pins, they were good.
 

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Unless you replaced the VVT solenoid with one of the following - ACDelco, Delphi, Standard Motor Products/BWD/NAPA Echlin, then I would be very suspicious of the VVT solenoid.

Rockauto has ACDelco, Delphi and SMP in the range of $27 - $58 dollars. The economy lines of VVT solenoids then sell are in the range of $17 - $26, and I would not touch any of the economy VVT solenoids unless it was an emergency.

Just something to consider.
 
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Discussion Starter · #16 ·
Unless you replaced the VVT solenoid with one of the following - ACDelco, Delphi, Standard Motor Products/BWD/NAPA Echlin, then I would be very suspicious of the VVT solenoid.

Rockauto has ACDelco, Delphi and SMP in the range of $27 - $58 dollars. The economy lines of VVT solenoids then sell are in the range of $17 - $26, and I would not touch any of the economy VVT solenoids unless it was an emergency.

Just something to consider.
Yeah, that is where my thought is currently, I just double checked, it was a no-name VVT solenoid that I used as the replacement. I just ordered an ACDelco VVT, I'll see what happens. I feel like it has got to be the VVT at this point, I've replaced or checked all components in the system.
 

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I'll keep my fingers crossed for you and before going to bed tonight, I'll swing a dead chicken around!
 

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Yes, when I replaced the phaser and timing chain components a couple weeks ago, I pulled it out and checked, cleaned it out as best as I could. The screens were about 99% clean, and I did apply voltage and heard it click, but did not check for any motion of the solenoid. I'll take a closer look at that and see if it's actually moving. The solenoid is, just a guess, 4-6 months old at this point, but it was not OEM, so could be problems. Yeah, I probed the pins, they were good.
its not always the screens of the vvts that get plugged. the passages can become gunked up also.
 

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2002 Pewter ls with automatic trans. 4x2, gray cloth interior.
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I've had P0013 & P0014 for years now. Finally decided I didn't want to deal with the rough cold starts and 10mpg gas mileage anymore. Below are the things I've done.
I've read countless threads here, as well as all the videos I could find on Youtube to try to solve this. I'm focused on the P0013 circuit malfunction, as this is likely causing the P0014 over advance condition, as the PCM is not able to control the solenoid/phaser.

VVT solenoid w/ oil change 3 months ago (generic)... no change

Camshaft phaser/timing chain replaced w/ oil change, one week ago... no change. The old phaser was crusted and locked up. It took some working with a pipe wrench to get it free. Once free, the spring tension was very low, so I suspect it had been not working for a very long time and had seized up.

Pulled the VVT and made sure the screens were clean, they were.

Swapped PCM, after a few cycles the codes were back, no change.

I've also probed the VVT solenoid harness pins, +12V on one and ground on the other. I've unplugged the harness from the PCM and checked for a short circuit to ground on the wires, and all was good. I've applied 12V straight from the battery to the solenoid and can hear it clicking just fine.

Here is what I plan to try in the next day or two....

Check the resistance on the VVT solenoid, should be 8-10ohms.

With engine idling, apply direct battery voltage to VVT solenoid. This should stall or stumble the engine, this will tell me that the system would work if it were to get voltage/command from the PCM.

If that tests okay, I will probe the harness, run the wires into the cabin with a spare solenoid and multitester, drive around to see if the PCM is actually sending the signal under normal driving conditions, however I'm wondering if the PCM will not do anything with the VVT circuit after the circuit is checked and the P0013 code is there, might need to clear the codes, then immediately take it for a drive.

Something I thought was strange was that I probed the harness, verified 12V, but the second the harness is plugged into the VVT solenoid, the voltage goes to 0, and the solenoid never clicks. A tech video that I watched showed that this was normal, so must just be how the PCM works with controlling the voltage & pulse, but just seemed strange to me, apparently that is normal.

Can anyone please give me your thoughts? I've spend so much time and $$ on this issue, I feel like I have to get it fixed.
I had the P0014 code as well and got a replacement from local auto part store OEM and ZERO issues since! I wasted money with 2 cheapo VVT's from amazon and even though the 2nd one still looked like new when I inspected it, that was still the main culprit for the P0014 in my case.

I'd change out both solenoids which are fairly simple with basic hand tools.
 

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Discussion Starter · #20 ·
I had the P0014 code as well and got a replacement from local auto part store OEM and ZERO issues since! I wasted money with 2 cheapo VVT's from amazon and even though the 2nd one still looked like new when I inspected it, that was still the main culprit for the P0014 in my case.

I'd change out both solenoids which are fairly simple with basic hand tools.
Which other solenoid are you talking about? I have the 4.2 I6, I believe there is only the one which controls the exhaust cam phaser.
 
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