32 CEL codes?!

Pierce Vaughn · January 25, 2020

Howdy all,

I’m looking for some help with a new to me truck, that looks like it has a few issues to fix. It’s a 2014 Silverado Z71, with just under 150k.

The problems I’m having so far are:

1. After sitting for a little while (hours -overnight) it turns over for several seconds before starting. If I just ran it, it starts normal.

3. sometimes driving it feels like it doesn’t accelerate or shift soon enough at slower speeds.

2. When going in gear it takes a while to go it seems like, or when switching from reverse to drive it seems to not start going immediately.

Two days ago I checked the codes and there was one for EVAP P0446 evaporative emission system vent control circuit , and P0430 (system efficiency below threshold bank 2)

This morning I go to start it and it turns over 5 or 6 times (about) and starts, and then the CEL starts blinking. I get the codes checked and here is what it has:

1. P0036 - heated oxygen sensor heater control circuit bank 1 sensor 2

2. P0037 - same as above but says circuit low

3. P0056 - same as above except bank 2

4. P0057 - same as above but says circuit and bank 2

5. P0138 - oxygen sensor circuit high voltage bank 1 sensor 2

6. P013A oxygen sensor slow response Rich to Lean (bank 1 sensor 2)

7. P013C -(Same as above but bank 2 sensor 2)

8. P0141 oxygen sensor heater circuit (Bank 1 sensor 2)

9. P014A sensor delayed response Rich to Lean, Bank 2 sensor 2

10. P0158 oxygen sensor circuit high voltage bank 2 sensor 2.

11. P0161 Oxygen heater sensor circuit bank 2 sensor 2

12. P0300 random- multiple misfire detected

13. P0430 Catalyst western efficiency below threshold bank 2

14.p0443 Evaporative emissions system purge control valve circuit

15. P0446 Evaporative emissions system vent control circuit

16. P0458 Evaporative emissions system purge control valve circuit

17.p06DA Engine oil pressure control circuit / open

18. P3401 cylinder 1 deactivation / intake valve control circuit / open

19. P3403 cylinder 1 deactivation / intake valve control circuit low

20, 21,22,23,24 and 25 are the same as the last two but for cylinders 4,6 and 7.

26. P0036 Heated oxygen sensor control circuit bank 1 sensor 2

27. P0037 Heated oxygen sensor control circuit low bank 1 sensor 2

28. P0056 heated oxygen sensor Control circuit bank 2 sensor 2

29. P0057 heated oxygen sensor Control circuit low bank 2 sensor 2

30. P0138 oxygen survivor sensor high voltage bank 1 sensor 2

31. p013A again

and a couple of the other codes again....

I’m assuming/hoping these are all related to a similar problem.
Fuel pump? I figured the evap and cat codes are a separate issue but not ruling that out.

Any help with this would be GREATLY appreciated. Thanks.

Lsgun1 · January 25, 2020

Start with the misfires. AFM codes and random multiple misses sounds like your going to be doing lifters.

davester · January 25, 2020

I hope you bought that truck cheap... Some of those things can be pretty expensive to fix.

I would first fix the oil pressure one, as personally, I'd like to know the oil pump is working every time the engine is started...

After that, I know GM recommends starting with the lowest code and working upwards (to higher numbers)..

Bash74 · January 26, 2020

Personally I would change the fuel pump out, reset codes and see what's up. Fuel pump problems can cause so many of those faults.

Sent from my SM-A505U using Tapatalk

Pierce Vaughn · January 27, 2020

Start with the misfires. AFM codes and random multiple misses sounds like your going to be doing lifters.

Well as far as the driving it seems to be acting fine the last couple of days. Wouldnt the lifters be a more catastrophic failure vs a come and go type of issue ?

Thanks for the help.

Sent from my iPhone using Tapatalk

Pierce Vaughn · January 27, 2020

I hope you bought that truck cheap... Some of those things can be pretty expensive to fix.

I would first fix the oil pressure one, as personally, I'd like to know the oil pump is working every time the engine is started...
After that, I know GM recommends starting with the lowest code and working upwards (to higher numbers)..

Okay Thanks.

I do believe the oil pressure code was most likely caused from whatever was making the truck have the fluke or weird running that more big when I started it and caused the engine to be below rpm and caused the oil pressure to drop Bc of the engine? That’s what I was thinking anyways. My oil pressure has been perfect.

Thanks

Sent from my iPhone using Tapatalk

Pierce Vaughn · January 27, 2020

Personally I would change the fuel pump out, reset codes and see what's up. Fuel pump problems can cause so many of those faults.

Sent from my SM-A505U using Tapatalk

I think I might do that. They are pretty easy to replace on these. It seems to be an intermittent problem. even though the codes are still there from when the i could definitely tell something was acting up. It’s been running perfectly fine the last day and a half.

I’m still going to figure out what happened, and let y’all know what I do. Still I find it hard to believe it threw that many codes. These newer trucks have so much going on. I’m used to the 90’s and 00’s Chevys lol.

Thanks for the help

Sent from my iPhone using Tapatalk

Pierce Vaughn · February 6, 2020

So it looks like the truck is having problems with the AFM cylinder lifters. (Which I guess is a problem on these AFM “capable” engines)

Basically the valves won’t close/open correctly because of faulty lifter(s) which messes up the fuel mixture and compression when the cylinder is supposed to be firing when it’s not in V4 mode. Which in turn is making the lean to rich codes, misfires, O2 codes and messing up the catalytic converter codes too... in addition to the codes for all the individual AFM cylinders.

So I have that going for me... I’ll update back when it’s done and I see what happens.

Sent from my iPhone using Tapatalk

Lsgun1 · February 6, 2020

Delete the AFM completely. Texas Speed and Performance sells a kit for it.

tbarn · February 6, 2020

At least 10 - 12 of your codes will not be AFM related. You have electrical issues and maybe more. When ever I had that many codes I would note them and delete them. Start over and see which ones come back. Their cannot be that many issues and not be primarily electrical. And there is "0" chance they are all related.

L86 All Terrain · February 7, 2020

32 code in one shot? Head problems? Park it in the hood with the keys in it. Make sure you have one of those magnetic key boxes on the frame with the cover gone. That way you can say you didn't leave the keys in it, they found your spare.

tlaw91 · February 8, 2020

Oh you just need battery cables most likely.

Super common. May as well be a maintenance item. That’ll cause anything and everything to set as a dtc. I would rule that out before starting anywhere else.

Hope this helps

-GM Tech

Sent from my iPhone using Tapatalk

Pierce Vaughn · February 8, 2020

At least 10 - 12 of your codes will not be AFM related. You have electrical issues and maybe more. When ever I had that many codes I would note them and delete them. Start over and see which ones come back. Their cannot be that many issues and not be primarily electrical. And there is "0" chance they are all related.

I know not all of them are related, the evap needs attention, and possibly the cats anyway. I did delete them and confirm which ones came back in what order and the AFM problem is definitely most of them. Also. Several of the codes were duplicates, just not confirmed. Thanks for the input. I’m sure I’ll spend more time running down some more issues after I’m done with this.

Sent from my iPhone using Tapatalk

tlaw91 · February 8, 2020

Well you were more concerned at the starting issue and alarming number of DTCs set at once so I thought we’d start there!

Hope that helped

Sent from my iPhone using Tapatalk

Pierce Vaughn · February 8, 2020

Oh you just need battery cables most likely.

Super common. May as well be a maintenance item. That’ll cause anything and everything to set as a dtc. I would rule that out before starting anywhere else.

Hope this helps

-GM Tech

Sent from my iPhone using Tapatalk

Funny you said battery cable, I did have to replace my short positive cable a few weeks ago that was bad. I turned the key and all the power went out to the truck. Cheap fix but was kinda unnerving since I had just bought it.

Sent from my iPhone using Tapatalk