Codes P0420 & P0430

[OR VietVet]

I think this spacer crap is just a patch that the dealer says should be done if aftermarket parts and it would keep the sensor from being mounted so far down in the exhaust stream.

 

[swathdiver]

I did buy the Delphi sensors

Have you ever heard of this spacer idea?

Yes, the spacers are usually used when one deletes the cats and retains the downstream sensors. If you search this forum you'll find a few posts of people having bad readings from Delphi sensors. I don't know why this is so, I know they make many parts for our trucks, like the nav radios. Put your old sensors back in and see if the trouble codes cease.

 

[h2100]

Yes, the spacers are usually used when one deletes the cats and retains the downstream sensors. If you search this forum you'll find a few posts of people having bad readings from Delphi sensors. I don't know why this is so, I know they make many parts for our trucks, like the nav radios. Put your old sensors back in and see if the trouble codes cease.

Well, Delphi used to be part of GM and I forgot that the original stuff is Delco, not Delphi.

 

[BG1988]

I did the new O2's. All 4. I was just going to repost that I will await new codes before anything is done.

P0228 is throttle position sensor/switch
(it's shorted to PCM)

that will trigger a P0420/P0430 code..

I had a broken MAF sensor trigger P0430 and P0420 codes


never got the MAF sensor code though..

Have had no issues or P0420/p0430 since replacement of that..

i would buy a code reader from walmart for 50$ and see if the CATs are actually heating up they should be about 350C-700C on these V8 engines. under normal running conditions

also check the freeze frame data for the long term and short term fuel trim mine spiked to 32+ then set the codes

 

[Mizz0313]

I replaced my bad cats with walker aftermarket and have got the p0420 and p0430 codes right after install and they never went away, here a year later and my truck is sitting as i cant get it inspected due to codes and I don't want to spend more money on another cat. I did replace o2's with delphi. Do you think its worth trying delco sensors instead? I honestly don't think these cats are bad as they where brand new and I've had the codes since I've installed it. Cats that were on the truck were so bad I couldn't merge onto a highway due to no power. Thinking of calling walker to complain. LOL.

 

[swathdiver]

I replaced my bad cats with walker aftermarket and have got the p0420 and p0430 codes right after install and they never went away, here a year later and my truck is sitting as i cant get it inspected due to codes and I don't want to spend more money on another cat. I did replace o2's with delphi. Do you think its worth trying delco sensors instead? I honestly don't think these cats are bad as they where brand new and I've had the codes since I've installed it. Cats that were on the truck were so bad I couldn't merge onto a highway due to no power. Thinking of calling walker to complain. LOL.

It's normal for the codes set during the first 100 miles or so as the new cats wear in. I would use ACDelco sensors and make sure the engine is in top form as a leaky injector or something can kill the cats. If that checks out, replace the cats.

 

[h2100]

I think this spacer crap is just a patch that the dealer says should be done if aftermarket parts and it would keep the sensor from being mounted so far down in the exhaust stream.

Well, here is chapter #5. The check engine light came on again with P060 codes (o2). I had them cleared and went about 5-6 days with nothing. To ensure they would stay off, i put in the bungs. Check engine light came on within hours. So, I'm not going to take them off and clear the codes. If light comes on again, i'll send the truck into the detroit river!

 

[OR VietVet]

Well, here is chapter #5. The check engine light came on again with P060 codes (o2). I had them cleared and went about 5-6 days with nothing. To ensure they would stay off, i put in the bungs. Check engine light came on within hours. So, I'm not going to take them off and clear the codes. If light comes on again, i'll send the truck into the detroit river!

Yep, that will fix the problem. Good call.

 

[h2100]

Yep, that will fix the problem. Good call.

Fingers crossed!!