stant_98

Hey all,

Well.. my check engine light came on again after the first time it happened in March of 2009. Then it was the first time ever it came on with the code P0430

P0430 Catalyst System Efficiency Below Threshold Bank 2.

I've got 122K on the car and take care of it very well - all sch. maintenance on time. Use premium gas and drive 80% highway.

Back in March my mechanic reset the computer and the light stayed off since. This time it came back on couple of days ago. The only thing I can think of is I may have gone too low on fuel and put another brand just $10 (expensive gas in that area) and after added my regular premium brand. Could it be that the computer can stay off for so long and then come back on... Well, duuhh, it can, but still what are your thought?

And yes, I've done engine and fuel flushes, and recent oil change and filters are new.

Thanks!

GEORGE_JET

Your description of the issue is confusing. So you had a P0430 code 9 months ago, and your mechanic cleared the code without repairing anything. Now 9 months later, the check engine light came back on. You did not mention if you checked to see if it is the same code???? In 9 months it could be anything. If it is P0430 again, then no, one tank of gas probably had no bearing on the current problem. Get the code checked, no point in speculating if it is even the same code after that long.

mmlex1987

^I agree, find out what the code is before you do anything.

stant_98

Mechanic checked it out today and he found the same code was displayed. I had him do a reset again. Will see how long it takes or may be it was bad fuel "Free State" - cheapest in town and they take cash only...

llcoolpass

bad fuel? are you kidding? that o2 sensor is probably shot, and that catalytic converter could also be bad too. your mechanic can test the 02 sensor or evaluate it's reading. i am a little stunned he is resetting the code and sending you on your way.

stant_98

Let me rephrase - I meant cheap fuel - not bad - as in leaded or bad. I put in 93 octane of the cheapest gas in town - that's all. And btw, this mechanic is my new mechanic and I did not tell me I'd already had check engine light come on with the same code back in March. I'd like to give this one more shot and see may be it will stay off this time. Mechanic says that there should be no performance issue: the car idles ok, gives me good gas mileage about 24-25 highway, engine sounds good, no vibration, nothing irregular. I wonder if, it could also, be salt, chemicals (in conjunction with cheap gas) that got stuck to under the car - I guess I'm fantasizing now...

stant_98

Anyway, just for future reference - what is the OEM part number for the catalytic convert that I may need. I assume that this is the cat on bank 2, which is the front pipe with the cat attached to it, am I correct?

stant_98

I wanted to follow-up on this and let you guys know that I found out that the catalytic converter for P0430 code is located at the front of the engine. Here is the email I received from a Lexus dealer:

...
We cannot reference the code for you but bank 2 refers to cylinder side 4, five, and six which on your car will be facing the grill.....

Part number
25052-20170

Price
293.92

This quote is from newlexusparts.com