: Can't seem to shake P0430 code N*



porkfarm
07-23-10, 08:06 AM
The weird thing is I can tell when the code is about to get thrown... The car run's the best it ever has. Smooth, quiet and powerful. Then 5 - 10 minutes later.. P0430 codes. 2 of them.

If I clear them, I can go a tank and a half before it happens again.

I did not clear codes this time, They might clear after 6 or 7 trips and my thinking is that the long term fuel trim might be getting reset with the clear ?

Here is what I have done to date. Has been a problem for 3 months now. Came up after the CPS was replaced, same side .

Replace rear O2 pass side.
Tighten intake
Clean TB
New stock air filter
Make sure oil is half way on stick ( and new )
89, 91 & 93 oct. fuel no change

Next step..

Swap O2 sensor with drivers side.
Take to dealer for cat converter.

Just strange that I can tell when it is going to throw the code. I wish it drove like that all the time... It's sweeet..

Maybe screwy code in the ECU ? My radio ( w/nav ) acts strange every now and then, but seems to reset itself.

Anyway... just throwing it out there, to see if anybody else is in the same boat or has a clue.

( I can't seem to say the word clue without thinking about southpark :histeric:)

Spyke
07-23-10, 08:09 AM
I'm pretty sure its just a bad cat.

porkfarm
07-24-10, 08:47 PM
Yup.. Swapped the O2's and it only took about 10 miles for the P0430 code to come back.. ( can almost always get it to go on after a filling the tank. )

Now all I have to do is convince Mr. Goodwrench that it is the cat.. Seeing as it is an aftermarket warranty, and the price of the new cat.. It should not be that hard.

BaTu
07-25-10, 10:17 AM
Don't all emissions items on the car come with a mileage warranty that often extends past what the manufacture gives?

How many miles on yours?

porkfarm
07-26-10, 05:23 AM
After I posted, I thought the same thing. it only has 66K on a 2005. Now I will have to fight them for the 95 buck diag charge.. even after I tell them what the code and issue is and what has been done to diag it. :helpless:

sts_meyers
08-03-10, 07:49 AM
I know it sounds crazy, but I had a very similar issue with my 2005 STS. I had to replace the gas cap. The oring must have had some leakage there or something. I got a aftermarket replacement cap, reset the codes, and have had no more problems with the codes. I would have though GM had a different code just for gas cap issues, but not in my case.

ewill3rd
08-03-10, 08:10 AM
No need to fight, the cats are covered for 8 years 80,000 miles.

For the record, bad oxygen sensors set oxygen sensor codes and oxygen sensor self tests MUST pass BEFORE the catalyst diagnostic can be run.
In other terms, if an oxygen sensor is faulty, the catalyst test will never run.
I applaud you for attempting to be thorough, but a P0420 or P0430 are pretty much no brainers. The only trick is to be sure that if something caused the cat to fail that it is repaired.

porkfarm
08-04-10, 01:50 PM
Service dept ordered CAT today.. I do have a Borla cat back system, so I wanted to make sure that the flange bolts where tight and no leak there. Sure nuff they snapped when I tried to get a turn on them... So .. new flange bolts and nice and snugged up.... Thowing codes like crazy. CPS & CAT codes now. CPS was swapped a few months ago. After those codes got fixed is when the CAT codes showed up. Maye that was the issue that fouled em up ? Maybe the loose intake bolts ? Maybe the GM top end cleaning that GM service did back at 50K ? Maybe the gas tank replacement issue .. ( even better than the gas cap ) . who knows ?

I will let you know after the cat gets replaced how it is going. Man that is not going to be a cheap fix.. but covered under 8Yr 80K by factory.

BaTu
08-05-10, 09:44 AM
My car has thrown CPS codes a few times and the dealer said they cleaned & greased the connector the first time I took it in. Next time, I thought it must be a bad sensor....

They said no, they just cleaned & greased that connector. SO,,,, they didn't just do Them ALL???? JUST the ONE the code pointed them to :) (I guess this leads to 4 repairs ;) it's all covered so, it's just the inconvenience)

Next time it happened, I did them ALL and haven't seen a CPS code in a year and a half ;)

porkfarm
08-16-10, 03:54 PM
New cat is in .. so far so good, but it will be a few weeks before I can give the ok if no more codes come up. I do not notice much yet, but it is running nice. ( always does after a code clear )

FYI. dealer replaced BANK2 for P0430 I was kind of shocked when it was the drivers side. I thought Bank 2 was pass side.

next2pool
08-17-10, 02:23 PM
New cat is in .. so far so good, but it will be a few weeks before I can give the ok if no more codes come up. I do not notice much yet, but it is running nice. ( always does after a code clear )

FYI. dealer replaced BANK2 for P0430 I was kind of shocked when it was the drivers side. I thought Bank 2 was pass side.

N* Cylinder and bank numbering are opposite of what most GM engines are for reasons we discussed in a previous post.