P0430 - bad cat converter efficiency - what to do?

[kj1962]

2006 V6 with 300K+ miles on it (original owner). My CEL came on the other day, but I was almost home, and for reasons I won't go into getting a tow would have been a huge problem at that time, so, knowing the risks, I drove home. The code was for a misfire on #6, so I replaced the ignition coil and cleared the code and everything was fine.

After 50 or so miles of additional driving, I'm now getting a p0430 for bad cat efficiency. Damn.

Where I live I'm not required to pass an emissions check. What are my options at this point? Haven't looked up the price for a converter, but I'm sure it's not cheap. Not wanting to put a bunch of money in at this point, since I think we're due for a new car shortly down the road.

 

[Buckaroo]

2006 V6 with 300K+ miles on it (original owner). My CEL came on the other day, but I was almost home, and for reasons I won't go into getting a tow would have been a huge problem at that time, so, knowing the risks, I drove home. The code was for a misfire on #6, so I replaced the ignition coil and cleared the code and everything was fine.

After 50 or so miles of additional driving, I'm now getting a p0430 for bad cat efficiency. Damn.

Where I live I'm not required to pass an emissions check. What are my options at this point? Haven't looked up the price for a converter, but I'm sure it's not cheap. Not wanting to put a bunch of money in at this point, since I think we're due for a new car shortly down the road.

Since you are not in an inspection state, I would ignore the code and keep driving it...no difference in performance. Since the CEL will be on all the time, check the codes periodically to make sure a problem does not sneak up on you.

 

[kj1962]

No further damage to the engine will occur from running on this bad CC?

 

[Jeebus]

I had a '04 V6 which threw P0420 & P0430, original cats. Unsure whether this was connected to the head gasket issue I had, not saying that you will have the head gasket issue because of your code.

I am in a non-emissions testing province, so I just cleared the code and reset it every time it popped up, probably once a week or so.

Not much you can do unless you replace some/all 4 of your cats. Could be your O2 sensors, but they have a different code when they start failing. I considered replacing my cats, but was thrown back by the price.

 

[Hungryhawk]

I suggest testing the O2 sensors before and after cat. There is a procedure to measure Ohms at specific temperatures to see if the sensors are accurate or going bad. A heat gun and IR thermometer are inexpensive and can ofter be borrowed.
Maybe it is not actually a cat issue?
Removing sensors from exhaust system is difficult.
I purchased my set of flex head ratchet box wrenches after messing with O2 sensors on my sisters vehicle. Thinking back these ratcheting wrenches might have been a big help.
Good luck with your project.

 

[Buckaroo]

No further damage to the engine will occur from running on this bad CC?

No - nothing bad will happen to the engine due to this code. This is all downstream from the engine. The O2 sensor after the CAT that generates this code does nothing to control the engine. It just monitors the efficiency of the CAT. The forward O2, in front of the CAT, provides control and monitors combustion efficiency and the output is used to make corrections. The second O2 sensor only exists to make sure the CAT is working properly. Ignore it and (if you are in a non inspection state), nothing of value is lost except a very small increase in exhaust contaminants because your CAT efficiency has been reduced.

 

[kj1962]

I suggest testing the O2 sensors before and after cat. There is a procedure to measure Ohms at specific temperatures to see if the

If this code hadn't come up just after having driven home with a misfiring cylinder, then I would suspect anything BUT the cat. But since I did that, I'm pretty sure it's the cat. Unless the misfire could have somehow damaged a sensor?

 

[Hungryhawk]

I assisted a family member trying to repair a 6.0L V8 in a GMC stake bed that was a lemon. It misfired a lot and somehow contributed to a shattered cat filling material and coated the exhaust system with a tan colored slurry of the tan cat matrix and moisture on start up.
What does inside of the tailpipe tip show as a coating? Is it clean, sooty with black, or some other material?

 

[4R005]

Had a P0420 code showed up after driving in 'limp mode' for about 2 miles to get home. While in LM small explosions were heard in the exhaust system ( my guess was unburnt gas were being ignited in cat ( driver side ). Changed downstream O2 sensor but no joy. I then installed a spark plug extender ( Amazon for $10. or less for two pieces. I bought the straight as well as the 90 degree elbow ones in case I ran into space issues. My ride is a '05 4R w/V8 ) to the O2 sensor which placed the sensor further away from the exhaust stream. Cleared CEL and cluster of traction control lights, VSC etc. Its been 2 years now and all is well, no CEL or other lites came back.
BTW, no testing where I lived. Also poured a good amount of Seafoam into gas tank ( maybe 1/4 full ) for good measure to clean up cat ( I cannot vouched if that help the cat but figured it would not hurt ). My $0.02

 

[Ralph Blake]

I agree with everyone saying just keep driving and keep watching how it drives and runs, spending the money to replace the many cats is just not an option.

 

[4R005]

[MENTION=35612]kj1962[/MENTION] If you have an IR thermometer reader ( at HF for $20. or beg/borrow ) check temps before and after cat. There should be a temp difference of about 100 degrees F, then your cat is good.

 

[MikeinNH67]

p0430 code means timing chain problem. I have been there. Replaced chain and everything is just fine for 5 years already. No codes even after using $4000 scanner.

You must be mixing up the number with a different one.

"A Toyota P0430 code indicates the catalytic converter on "bank 2" (the side of the engine opposite the number one cylinder) is not operating efficiently."

 

[Jeebus]

You must be mixing up the number with a different one.

"A Toyota P0430 code indicates the catalytic converter on "bank 2" (the side of the engine opposite the number one cylinder) is not operating efficiently."

Correct.

I just did a quick google and it shows that a timing chain related code would be P0016, P0017 and P0340.

 

[Runnin on E]

It would be nice if this forum had a "search" function conveniently located at the top so everyone could see it (and use it) Gosh that would be nice....

 

[jmoore15]

Bad cat

I've had the same issue and wondering if its worth it to fix my 4runner with 240k

 

[jmoore15]

Cause

what causes a cat to go bad? some seem to last forever but some die

 

[MikeinNH67]

what causes a cat to go bad? some seem to last forever but some die

In the case of the p420/p430, I wouldn't go so far as a bad cat as the code is for inefficiency. An exhaust leak can cause the code as can an old O2. Only other option is a cat that is getting tired. Could be dirty or the metals inside could be less effective, the computer sees the exhaust gasses as out of it's parameters and sets the code. Adding a non-fouler to space the O2 out a bit has been known to be a work around.