Jump to content
  • Sign up for FREE! Become a GM-Trucks.com Member Today!

    In 20 seconds you can become part of the worlds largest and oldest community discussing General Motors, Chevrolet and GMC branded pickups, crossovers, and SUVs. From buying research to owner support, join 1.5 MILLION GM Truck Enthusiasts every month who use GM-Trucks.com as a daily part of their ownership experience. 

ChevyTuff

2013 Sierra 1500 PO420 Code

Recommended Posts

8 hours ago, ChevyTuff said:

Swap the Front, not the Rear sensors? Also, on the battery, I was getting the PO420 code before I changed the battery, but I'll have this new one checked.

I doubt P0420 has anything to do with your battery.  All of those other problem could be associated with a bad battery or grounds.  Some problems seem to be related but you have multiple issues going on here.

Share this post


Link to post
Share on other sites

I swapped the Front 02 Sensors last night. I'll drive to town today and see if that P0030 code comes back. Where can I buy one of those Tech-2 meters?

  • Like 1

Share this post


Link to post
Share on other sites
45 minutes ago, ChevyTuff said:

I swapped the Front 02 Sensors last night. I'll drive to town today and see if that P0030 code comes back. Where can I buy one of those Tech-2 meters?

Ebay usually, look for US sellers but some of the Chicom ones are reputable and have good reviews.  Can also buy from ChinaCarDiags and places like that.  They run $300-$350 or so.  Make sure software is 33.004.

 

Is your Sierra an NHT by chance?

Share this post


Link to post
Share on other sites
1 minute ago, swathdiver said:

Ebay usually, look for US sellers but some of the Chicom ones are reputable and have good reviews.  Can also buy from ChinaCarDiags and places like that.  They run $300-$350 or so.  Make sure software is 33.004.

 

Is your Sierra an NHT by chance?

I just watched a video on the GM Tech2, and it looks like I would be wasting my money unless I took a course on how to use it. I only have Apple Mac and iPd also. 

Share this post


Link to post
Share on other sites
2 minutes ago, ChevyTuff said:

I just watched a video on the GM Tech2, and it looks like I would be wasting my money unless I took a course on how to use it. I only have Apple Mac and iPd also. 

It's not hard to learn, I didn't take any classes, just bought and used it.  If you need to do programming, then you can connect it to the internet at ACDelco's TDS system.

Share this post


Link to post
Share on other sites
Posted (edited)

Well, I took my truck to the Chevy Dealer in Missoula (Karl Tyler) and here's what they're telling me. They found the oil. cap missing, I have no idea what happened to that. They say this could set off codes and there was a code on bank 2. They cleared the codes.

 

They are saying that the Cats I had installed are not original GM Cats, and that I need to install the factory Cats. I paid almost $600 for these Cats, and paid a muffler shop $250 to install them. They told me the parts alone for them to install GM Cats is over $1700

 

Edited by ChevyTuff
  • Like 1

Share this post


Link to post
Share on other sites

Not having factory cats won't cause a misfire code or an upstream o2 sensor code.

 

Only if you are still getting a P0420 or P0430 would it need OEM cats. But at that point there is no way I'd spend $1,700 for new cats when you could just tune the computer and shut off those codes forever for like 1/3 the price.

  • Like 1

Share this post


Link to post
Share on other sites

 

This is my bill from our dealership. 3 pages, so I will have to do 3 posts

1467874676_ScreenShot2021-03-30at6_03_46PM.thumb.png.b18857779cde6fadffaf15bb0e4c8fcd.png$1000.00 and they say now that it's the aftermarket Cats causing the problem. And the codes are still on.

 

Share this post


Link to post
Share on other sites
Posted (edited)

So this is where it stands now. They found Codes PO523 / PO155 / POO59 and POO50  ..... All on Bank 2 Sensor 1

They charged me 8 hours labor total, and they did not find the main problem with the mis-fire. Most of the $800 plus labor was their diagnosing the misfire, and they didn't fix it. They blame it on the after market cats.

I am happy with the tranny flush, and the door wire fix.

 

Tell me what you guys think. I am desperate here.

 

 

Screen Shot 2021-03-30 at 6.13.24 PM.png

Edited by ChevyTuff

Share this post


Link to post
Share on other sites

The part about needing new cats still doesn't add up to me. If the fuel trims are still negative that means it's running rich on that bank. That can be caused by the misfires. Now if the bank 2 sensor 2 is reading really low mv that would mean that the sensor is showing lean.

 

Values of like .900mv is rich and ~100mv is lean. How can the front o2 sensor report negative fuel trims (rich) but the rear o2 sensor report lean??

 

I have never seen new cats fix that problem. The only codes that should make the SES light come on from non working cats are the cat inefficiency codes themselves.

  • Like 1

Share this post


Link to post
Share on other sites
Posted (edited)

I have to agree that the Cats are  probably not the culprit. Everyone I have talked to has said these after market Cats work just fine. I don't know what to do at this point. I arguably paid the bill and picked up my truck today. It still misses and runs crappy just like before, especially when I drive it, then park for a while, then drive it again. Code P0050 was reset when I parked it and started it again at home. 

Could it possibly be something like one of these and the shop tech just doesn't know what he's doing?

 

 

Screen Shot 2021-03-31 at 6.50.01 PM.png

Edited by ChevyTuff

Share this post


Link to post
Share on other sites

Seems to me they charged 1.0hr diag. $139.00. Roughly $800 was spent on oil pressure sensor replacement, trans flush and wiring repair. 

P0050, P0059, P0155 are all bank 2, sensor 1 heater codes. Shouldn't cause a drivability problem especially on a warm engine. Cats could not cause these codes. Pull the passenger side oxygen sensor in or near the manifold. Is it soot covered? possibly a leaky injector ( internal ). Here is a schematic for oxy  sensors  if it helps.

 

 

2757999.jpg

Share this post


Link to post
Share on other sites

I just had the 2 front sensors out and swapped them around. I didn't see any oil on the sensors, and they are brand new Delco sensors. Something is causing it to set the codes and to run very poorly.

Share this post


Link to post
Share on other sites

These 3 codes can only be caused by a bad sensor, wiring or ECM. You or someone needs to do a deep dive diagnostic. Whether or not they cause a rough run condition is another question.

  • Like 1

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.




×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.