P430 Error / Cat Question.

OK, the check engine light comes on and my handheld says its a P430. I reset it and it comes back on. I take it in they say its the cat. So they replace two cats, reset the light and send me on my way... About 30 miles later and check engine light comes back on. Then I check the O2 sensors. So $600 plus for the first cats and more for the O2's and the check engine light is still on!

Now they are telling me $3,000 to replace additional front 2 cats... I'm done with it. No guarantee that will keep the light off. I just want the light off to pass inspections. Not dumping $3,000 into a truck that is running fine and doesn't appear to be polluting any more than the average car on the road. Any ideas how to get the check engine light off? Looking at using spark plug defoulers to pull the O2 sensors back out of the pipe a bit. Anyone had luck with this? Or any other ideas? Is an 02 sim another option, or better option? Thanks!

 

Are you still under Emissions Warranty?

 

Sounds like you're being taken for a ride. How many miles do you have on your truck? Any engine mods? The O2 sensors usually go bad well before the cats and can cause a the same P0430 code.

 

Isn't P0430 covered by emissions warranty?

 

Sorry, been running... I believe it is a P0430. I was told Cats. But hasn't fixed it. The truck is an 06 TRD with 130K on it. So out of any warranty. I'm going to go double check the code.

 

Vlaude ~ try this link:
If the code is a P0430, it's the exhaust manifold (3-way cat) which is at the front, not the rear cats and it has nothing to do with the O2 sensors if the codes are not being thrown for an O2 sensor (in my experience). I've attached a picture for reference. The red circles are the parts I'm assuming the dealer replaced on your truck??? The yellow are the two front cats that go into the manifold. The code throwing could be caused by a few things that were either free or cheaper and easier to fix. Before taking it back to the dealer for anymore work, check to see if you have leaks in the exhaust system around the cats circled in yellow. Air leaks or gas leaks will cause the CEL to come on. Drive it around for about 5 mins. and check the tailpipe to see if it's condensation (normal) dripping or if it a mixture of gas and condensation (not normal). If there's a mixture, it's a leak somewhere in the system. If it's not that, try the A/F sensor. If it's not that, check the O2 sensors. Again, if it's not throwing the codes, I don't believe it would be those... Final fix is changing the manifold. Another "trusted" mechanic should be able to do it so much cheaper than the dealer.

IMO, a good dealer would've checked all of this before replacing anything that didn't have to do with that code. If it were me, I would take it back to the dealer with these sheets (because this is part of the actual service manual) and have a few nice words with the GM.
Make them show you what tests they performed and why they decided to change the rear cats when the service manual shows that's not the problem. Damn stealerships!

 

Picture attached.....

 

Sorry to revive this but....


My 05 v6 threw the p0430 code. I've cleared it with hand held but it comes right back. I am actually overdue for my emissions test (last month, stupid state no longer sends mail notification that registration is expiring). My state supposedly does odbII test but in the past I've taken it in and they just put the sniffer in and wave me through without bothering with the odb bit. I'm pretty sure I can squeak my way through emissions the way I am now (if not I've got some other tricks of the trade )

My question is: I'm thinking about getting DT long tubes and the o2 simulators. Assuming the possibility that I have a bad cat which if I'm reading everything correctly would have been one of the upper manifold cats which are deleted with the DT long tubes will I still need to replace the upstream sensor driver side? I know this isnt legal for street use so no lectures please.

**Hey Folks, heres an update if anyone cares

In delaware they dont yet do ODBII testing on the vehicle (at least not in my county), so all I had to do was pass the sniffer test. I used my scan tool and determined at least in my opinion that the second oxygen sensor is faulty using the test procedures from the manual. Because of this i figured that the CAT is probably still good and took a chance and just went through emissions. Passed with flying colors. I think rather than replacing the second sensor i'm just gonna save a bit more money and buy the dt headers