catalytic converter problems with cheap gas? P0430

[hans747]

Hey Guys,

Earlier this year, i started getting an intermittent P0430 code on my 2002 V6 (that's the code that says the cat converter is not performing up to snuff). I took the advice of someone on our MB and installed a nonfouler (in vancouver now......enroute P0430 with history!). But the problem persists.

During this time, I noticed that the light is on when I'm burning a tanks of gas that I buy from the grocery store's gas station. When I go to the new Shell station across the street, the light eventually turns off.

Has anyone else had similar problems?
Is this a sign that my catalytic converter is on the way out?

Thanks

[leakyseals]

Need info to determine if cats on its way out.

miles?

Oil consumption?

City or highway use?

Use of cleaners/additives in fuel like seafoam, MMO, etc?

[hans747]

Originally Posted by leakyseals

Need info to determine if cats on its way out.

miles?

Oil consumption?

City or highway use?

Use of cleaners/additives in fuel like seafoam, MMO, etc?

120,000 miles
No oil consumption to speak of.
It spends about half its time on the highway and half in town driving.
Never used any cleaners or additives aside from maybe a bottle of Techron once a year.

About a year ago, i replaced the upstream O2 sensor on this bank (this is the firewall set of exhausts).

[leakyseals]

I have an 02 XLE 2.4 I4. Went through this problem last 2 years. Lot of research over that time. Will tell you the resolution, maybe you can use some of it. Would suspect there are some similarities. I got the code, intermittent and random at first, usually on the highway. would go out with around town driving. Eventually stayed on Found out there was a TSB for the 2.4 to correct this, covered up to 80k. New cat with a different media, and a ECU reprogram (assume a different threshold) Never checked if this effected the v6 as well. I found this out after performing a number of things to make the light go out. Here's what I know now.

The original factory programmed threshold for P0430 CEL is when cat goes below 90% efficiency. Means IMO if there's no blockage or performance issues, the cats still good, just a little more pollution. The main problem is inspection. The downstream o2 sensor is the one that triggers the code. Because its farther away from the engine, its has less ability to clean/burn off carbon. Cleaning downstream o2 with TB cleaner followed by MAF sensor cleaner can stop the light "for a while". DO NOT use seafoam deep creep, or any lubricant based cleaner on the sensor, will make things worse. Using an aftermarket cat makes the light go out "for a longer while". For the reasons stated above, the CEL is triggered by a specific media, and a specific threshold.

resolution: order toyota cat (with gaskets) from toyotapartseast.com. Have mechanic install. Go to dealer, pay for reprogram.

What you should do.

1) Clean downstream sensor
if that doesnt work...
2) check for TSB
if you dont have one...
3) buy replacement cat and gaskets from toyota (no afternarket). Have your mechanic install.

[leakyseals]

Forgot to mention, my cel went off at 120k. Had oil consumption issues and poor tuneup maintenance from prior owner which were resolved prior to new cat.

[hans747]

That's all very helpful information! Thanks

[hans747]

a month and several gas tanks later, I've just started buying gas from Shell. The light stays off. If I buy from the grocery store or a cheapo convenience store, it's back on in a day. Whatever. I don't think I'm going to own this car for more than a year. So much piddly crap going wrong with it (the last three months have been a starter, alternator, another window motor, now THIS). I'm just going to drive it on good gas until it's time to trade in. Sad part is that this car has enjoyed a pretty charmed life. I expected better out of Toyota.