CEL for P0420, P0430, P0171, P0131, P0134

[thefrey]

Recently threw these codes. They have been on the backburner with other issues I have been dealing with. It recently started right before my DOD delete with just the P0420 and P0430 and i was running e85. Then I picked up the other 3 after clearing it.

I don’t have a code scanner so I’ve just been using auto part store scanners to read/erase codes.

Does this magical concoction of codes tell anybody anything? It seems like to me it points to a failing O2 sensor but I don’t have any way to read it with a multimeter/scanner.

 

[Fless]

Is the 2013 6.2L engine a Flex Fuel engine? If not, running E85 would cause it to run lean.

 

[thefrey]

Is the 2013 6.2L engine a Flex Fuel engine? If not, running E85 would cause it to run lean.

Yes, it is a flex fuel engine

 

[thefrey]

Wanted to bump this thread to see if anybody has any ideas.

The P0131 is intermittent and sometimes comes and doesn’t.

I am thinking that it makes sense to replace my upstream bank 1 sensor since the code is being thrown specifically for that one. I would think a true vacuum leak would throw a code for both upstream o2 sensors perhaps?

 

[Fless]

You really need a scanner -- even a cheap one that would show some live data would help.

What are the short- and long-term fuel trims, both at idle and at 1800 rpm or so?

The "true vacuum leak" could be on one bank. But you can swap the upstream O2 sensors side to side to see if the code moves banks.

How old are the O2 sensors? And they're best changed in pairs, using OE GM sensors, if available.

 

[thefrey]

You really need a scanner -- even a cheap one that would show some live data would help.

What are the short- and long-term fuel trims, both at idle and at 1800 rpm or so?

The "true vacuum leak" could be on one bank. But you can swap the upstream O2 sensors side to side to see if the code moves banks.

How old are the O2 sensors? And they're best changed in pairs, using OE GM sensors, if available.

I can only assume they are original O2 sensors.

I am going to try to get live data borrowing a parts store scanner to see if that’ll tell me anything. I just would think the P0134/131 would only show up if the o2 sensor was having issues.

Doing diagnosis like this new to me so it’s a shot in the dark most of the time but there’s always something to learn.

 

[OR VietVet]

Yes, like @Fless said, O2's, pairs only and IMO, GM or Delphi.

 

[thefrey]

Yes, like @Fless said, O2's, pairs only and IMO, GM or Delphi.

Is the pairs meaning per side/bank, or would I need to replace the other upstream in this scenario?

 

[OR VietVet]

Is the pairs meaning per side/bank, or would I need to replace the other upstream in this scenario?

Either both upstream or downstream. Depending on where you live and salt on the winter roads, crawl under and spray penetrant 2-3 times a day and then remove the next day.

 

[opfor2]

Make sure that you stick with real OEM upstream O2 sensors one of the cheapest places to get them is from RockAuto.

 

[thefrey]

I went ahead and installed 2 new GM upstream sensors. Didn’t have time to order from rockauto unfortunately but advanced auto had 20% off. Traveling for the holidays and out of state so laying on the parking lot of the auto parts store had to do for now

 

[thefrey]

Seems like the p0420/0430 is lingering a bit. I have only driven about 20 miles since the new o2 sensors and had the 420/430 code come on at a stop light in the first 5 or so minutes. Seems the 171/131/134 isn’t there at the moment. I don’t know if it’s something with the fuel trims not being adjusted yet? Going to try to run the car more later to hopefully do a relearn on the fuel trims

 

[Fless]

A good scanner can reset the long-term fuel trims so it would start from 0. If not done, it will take driving it with various engine speeds and loads to correct the different fuel maps.

 

[thefrey]

A good scanner can reset the long-term fuel trims so it would start from 0. If not done, it will take driving it with various engine speeds and loads to correct the different fuel maps.

Dang. The scanner I was borrowing from the parts store was solid. Will have to go back perhaps.

I can say that my long term fuel trim1 was 9.4 and 2 was 4.7

 

[Fless]

Ok, but to get true fuel trims each bank's short- and long-term trims should be added together.

 

[j91z28d1]

without looking it up, what do the codes mean? I'm being lazy to search each one.

and borrowing a scanner all the time is a lot man. the the little gear wrench dongle and phone app does as much as most low to mid range scanners. Last I looked Amazon had a sale for 130$. hard to own a old vehicle with no scanner.

get the little more expensive pro one instead of the cheaper diy one. you wanna be able to read and see data from every module.

a miss fire can make the o2 readings go wacky too. ate you still getting miss fire counts?

 

[07burban88]

how's the truck running? any struggling for power or can ya full send it? may be bad downstream sensors. the bad upstreams lying to the ecu could have messed with readings sending more fuel killing the downstreams. i had cat codes on the 07, changed the downs and passed emissions test

 

[thefrey]

how's the truck running? any struggling for power or can ya full send it? may be bad downstream sensors. the bad upstreams lying to the ecu could have messed with readings sending more fuel killing the downstreams. i had cat codes on the 07, changed the downs and passed emissions test

It’s honestly running great. I just did a DOD delete and have driven it almost 2k miles and ironing out some things. I don’t feel any lack in power that I can tell. I am also currently at 6500ft instead of my normal 500ft ish so I can feel a little bit of loss from altitude but by no means do I feel anything sluggish

I also have not really had any loss in MPGs from what I can tell

I don’t have emissions testing but I still would like to try to figure out the problem. The sensor possibly going bad and dumping more fuel into the engine doesn’t give me a warm fuzzy feeling long term

 

[thefrey]

without looking it up, what do the codes mean? I'm being lazy to search each one.

and borrowing a scanner all the time is a lot man. the the little gear wrench dongle and phone app does as much as most low to mid range scanners. Last I looked Amazon had a sale for 130$. hard to own a old vehicle with no scanner.

get the little more expensive pro one instead of the cheaper diy one. you wanna be able to read and see data from every module.

a miss fire can make the o2 readings go wacky too. ate you still getting miss fire counts?

420/430 cat efficiency, 171 lean bank 1, 134 no activity detected sensor 1 bank 1, 131 low voltage sensor 1 bank 1

Probably should have mentioned that lol

Yeah I need to get a scanner. Running to the parts store to borrow them has been fairly easy but there’s a lot of options as far as scanners and I don’t want to drop a decent amount of money into a scanner or buy a cheap one that needs a subscription

Not sure on misfire count

 

[swathdiver]

Recently threw these codes. They have been on the backburner with other issues I have been dealing with. It recently started right before my DOD delete with just the P0420 and P0430 and i was running e85. Then I picked up the other 3 after clearing it.

I don’t have a code scanner so I’ve just been using auto part store scanners to read/erase codes.

Does this magical concoction of codes tell anybody anything? It seems like to me it points to a failing O2 sensor but I don’t have any way to read it with a multimeter/scanner.

For starters, the lowest two codes are for the driver's side upstream oxygen sensor.

There's three possibilities here as to why it's throwing codes, the sensor is no good, the wiring needs repair, the ECM is needs replacing. Solve this and the P0171 will probably go away.

You at least need a good OBDII adapter that can clear codes and show you all the engine data.

I use BT and WIFI Foseal ODBII adapters and pair that with my Android phone and the Torque Pro app. My kids have IPhones and use the CarScanner app from the Apple Store, it's free for them. I paid $5 for mine about 8 years ago.

I can only see engine stuff with my phone and app, my kids can see ALL codes from anywhere in the car and clear them with their IPhone and app.