P0430 Code, Bad Cat?

**kool-aide** · 06-14-2008, 05:52 PM

I threw P0430 on the way home today. Noticed a little miss or something funny while on the highway, nothing real bad. Since I have poly motor and trans mounts I couldn't really tell if it was running rough, cuz every day is a rough ride, lol...

I have probably 5k miles on the plugs and wires, quiet possibly less, can't remember. I know I have less on the fuel filter, I think. Crap I should write this stuff down, lol...

Well My car used to throw codes last year, but never had them read and they went bye-bye on their own. Now I have a reader, thus I know the code.

I didn't notice a bit of smoke yesterday during a nice highway acceleration. I was being tailgated by a knuckle head in a truck with a lift kit. We were at about 65, i may have slowed to 60, and then i took off for a few seconds.

In the rear mirror i saw smoke, not something I can say I have seen before.

I plan to erase the code and see what happens. I'm also thinking of the brake booster sea foam treatment.

So what do you guys think? Think I screwed the cat? Ok that just sounds real bad.

BTW, 102k miles, stock exhaust, O2s, CATs, ECM/PCM you get the picture.

thanks

kool-aide

**Cutlass** · 06-14-2008, 06:28 PM

p0430 means you have a bad cat. Seafoam isn't gonna do crap for a bad cat.

**kool-aide** · 06-14-2008, 07:02 PM

I agree sea foam won't fix anything. I'm just asking if the code means bad CAT. The description implies the CAT is not operating efficiently, wrut wrow shaggy. Could be something is obstructing the flow, fouled plugs, or really a bad CAT. I'm not ready to drop money on a CAT if it could be something else. I also remember my last plug install, not fun, lol...But no worse than front shocks.

I did a couple of more "spirited" drives today and the car was fine. I didn't watch the mirror so I can say if there was smoke. It was the ride home that I saw the SES come on. That would be post nut case screw ball spirited driving if you follow.

Maybe it is pissed because we went to Daytona and didn't ride the track?

**Cutlass** · 06-15-2008, 08:06 AM

Well P0430 can really only mean there is a problem with the cat, an exhaust leak near the cat, or an O2 sensor problem. I've personally never seen or heard of a P0430 that wasn't caused by a bad cat converter.
The smoke you've been seeing could cause the converter to fail quicker then expected. If the smoke is caused by burning oil, rich A/F ratio, or burning coolant, all can foul up a cat.
If you don't wanna spend the money for a new converter and you don't have emission testing, you could get an o2 simulator. They come in 2 forms, electrical and mechanical. I put a mechanical one on my old '95 Blazer with a gutted converter and it worked fine. It is illegal though

**kool-aide** · 06-15-2008, 12:22 PM

I'm in FL, no inspections,

.

Well the code hasn't come back on. I guess I will have to wait and see how it does.

If I had to replace the Cats I would prefer 2000-2002 setup. I don't know if I'm thinking of 2000 or 2001-2002. Any way the point is I don't like having my P/S cat welded in.

I noticed Magnaflow / Car Sound makes a replacement that seems to be a two piece slip fit setup.

But if i was going to spend all that money on two new Cats from Catco or Magnaflow setup. I'm already at 400 something bucks. Kind of puts you in the ball park for headers and y-pipe at that point, lol... I don't think I could sleep at night running an ORY.

Who knows, I will see what happens this week.

**qwk93ta** · 06-16-2008, 01:27 PM

You have a 10 year 100k or 120k warranty on your cats from GM. I had my driver's side replaced a few months ago.

**2001NBMZ28** · 06-16-2008, 01:37 PM

The 10 year/120K extension on cat warranty is only on the '00-'02 cars.

**Cutlass** · 06-16-2008, 04:50 PM

Originally Posted by qwk93ta

You have a 10 year 100k or 120k warranty on your cats from GM.

nope, that not true.

Originally Posted by 2001NBMZ28

The 10 year/120K extension on cat warranty is only on the '00-'02 cars.

^^^^Correct!!^^^^

**kool-aide** · 06-16-2008, 05:26 PM

well I have made it one day with no SES. Let's see how long I can limp along.

thanks guys

**FORMULA7** · 06-18-2008, 03:18 PM

Ive had the PO430 and the PO420 code.I also have reseted the code and sometimes it comes back within couple miles.I do have Magnaflow Highflow conveters on a Y pipe tho.Some people have told me its a bad cat,which I don't quite agree totally.Bought them back in Feb.If I did both should have went out.Don't know.This post might not a have any revelant info to your post.

**kool-aide** · 06-18-2008, 03:57 PM

Originally Posted by FORMULA7

Ive had the PO430 and the PO420 code.I also have reseted the code and sometimes it comes back within couple miles.I do have Magnaflow Highflow conveters on a Y pipe tho.Some people have told me its a bad cat,which I don't quite agree totally.Bought them back in Feb.If I did both should have went out.Don't know.This post might not a have any revelant info to your post.

Hmm, that's interesting. Are you saying you got P0420 and 430 on the Magnaflows?

**kool-aide** · 06-18-2008, 03:58 PM

Well, cross my fingers, still running code free.

**FORMULA7** · 06-18-2008, 08:55 PM

Originally Posted by kool-aide

Hmm, that's interesting. Are you saying you got P0420 and 430 on the Magnaflows?

The code P0420 came up only after I say 2 months after I bought and installed the cats.The P0430 came up only once that I know of.I did however replaced the left top o2 sensor Bank 1 and it seem to have stop the code from coming back often.The code comes on after a few hundred miles.In my occasion after 150+ miles and sometimes after 80+ miles.I think I may be putting up more miles than usual on my odometer as I have installed gears.Don't know how really miles Im putting up.

**FORMULA7** · 06-18-2008, 08:56 PM

Originally Posted by kool-aide

Well, cross my fingers, still running code free.

How many miles since you last reset the code?

**Redphoenix1998** · 06-18-2008, 09:16 PM

There could be a couple of things so don't blame the cat right away. You probably haven't thrown the code yet because you haven't run all the criteria to properly run the cat monitor. If it has run then you're in the clear. To check the cat monitor hook up your scanner, check I/M readiness or monitor status and scroll till you see cat monitor. If it says no done or incmp keep driving till that monitor runs. Once it runs the code can come up again. Also you could have a "lazy" O2 sensor that can fool the pcm into thinking it's a bad cat.

**kool-aide** · 06-19-2008, 03:00 PM

Originally Posted by FORMULA7

How many miles since you last reset the code?

i didn't know there would be a test.

Hmm, I drive like 13 or 14 miles one way to work. For simple math lets call it 30 a day. M, T, W, Now Thursday. I would estimate 125-130. No that's not bad math. I did a little spirited driving when I sea foamed on Sunday.

How many miles should I wait before declaring victory?

**kool-aide** · 06-19-2008, 03:03 PM

Originally Posted by Redphoenix1998

There could be a couple of things so don't blame the cat right away. You probably haven't thrown the code yet because you haven't run all the criteria to properly run the cat monitor. If it has run then you're in the clear. To check the cat monitor hook up your scanner, check I/M readiness or monitor status and scroll till you see cat monitor. If it says no done or incmp keep driving till that monitor runs. Once it runs the code can come up again. Also you could have a "lazy" O2 sensor that can fool the pcm into thinking it's a bad cat.

I will give that a whirl on Saturday, maybe Friday night. I have always wanted to use my scanner for something more than a paper weight, thanks.

Would it be the rear O2 if that was the lazy one?

Would certain values in the tool indicate which O2 is not up to par?

I mean there are a lot of parameters and such, and I have no clue what any of them mean. I could spend hours searching the web, oh joy.

thanks