P0430

[antony80]

MY 99 GS4 HAS THE CHECK ENGINE LIGHT ON FOR THE SECOND TIME IN 2 WEEKS. FIRST TIME IT WAS MY BANK1 CAT CONVERTER COST AT THE DELEARSHIP $1600. NOW THE OTHER CAT(BANK2) IS BAD ACCORDING TO THE DEALER.

I DON'T WANT TO SPEND OTHER $1600 ON MY CAR. I HAVENT DONE MY TIMING BELT OR MY SPARK PLUGS ON THIS GS4 YET. I HAVE 86K MILES.

QUESTION:

IF I CHANGE THE SPARK PLUGS AND DO THE TIMING BELT AND RESET THE CODE BY UNPLUGING THE BATTERY FOR 15MIN(WILL THIS RESET THE CHECK ENGINE LIGHT?) WILL THIS SOLVE THE PROBLEM? OR DO I REALLY HAVE TO SPEND $1600 ON THE OTHER CAT CONVERTER?

PLEASE HELP. I AM IN A LOT OF PAIN SINCE I ALWAYS PRAISED LEXUS AS THE MOST RELIALIABLE CARS ON THE ROAD. I LOVE THIS CAR SO I DON'T WANT TO TRADE IT IN..H E L P.

[jarvis]

MY 99 GS4 HAS THE CHECK ENGINE LIGHT ON FOR THE SECOND TIME IN 2 WEEKS. FIRST TIME IT WAS MY BANK1 CAT CONVERTER COST AT THE DELEARSHIP $1600. NOW THE OTHER CAT(BANK2) IS BAD ACCORDING TO THE DEALER.

I DON'T WANT TO SPEND OTHER $1600 ON MY CAR. I HAVENT DONE MY TIMING BELT OR MY SPARK PLUGS ON THIS GS4 YET. I HAVE 86K MILES.

QUESTION:

IF I CHANGE THE SPARK PLUGS AND DO THE TIMING BELT AND RESET THE CODE BY UNPLUGING THE BATTERY FOR 15MIN(WILL THIS RESET THE CHECK ENGINE LIGHT?) WILL THIS SOLVE THE PROBLEM? OR DO I REALLY HAVE TO SPEND $1600 ON THE OTHER CAT CONVERTER?

PLEASE HELP. I AM IN A LOT OF PAIN SINCE I ALWAYS PRAISED LEXUS AS THE MOST RELIALIABLE CARS ON THE ROAD. I LOVE THIS CAR SO I DON'T WANT TO TRADE IT IN..H E L P.

man i know exactly where youre coming from. i have the same problem on my 2000 gs3. i replaced both cats and the check engine light came back on.

[flop170]

p0430 and p0420 are catalyst ineffiencys or something like that.... one for each bank.... this either means the cats are bad or not there anymore or the o2 sensors after the cats are bad.....

[JDMSedan]

Damn! I really wish you didn't spend $1600 on a cat that you probably didn't even need. Just because you get a catalyst efficiency code it doesn't mean you need to replace the cat. Let's see, you replaced the cat and you still have a problem. What that tells me is that something else is causing your cats or better yet your secondary O2 sensor to generate a higher voltage than the factory set parameters are allowed to see. OBDII codes are not designed to tell you exactly what the problem is with your car, it just gives the technician a general area to look in. Something is causing an extremely lean or extremely rich condition in your engine which is causing the cat to have to work harder than it needs to. I garantee if you put another cat on you car you may stand the chance of ruining the new one over a short period of time. Did the technician even hook up a scanner to your car? WTF? BTW p0430 and p0420 codes mean. 1st digit = Powertrain problem. 2nd digit which is 0 means a generic code (meaning not manufacturer specific), the 3rd is some sort of emission control problem (possibly the cat but not definite), and the last two are specific to your car's systems. I hte to tell you this, but you may have wasted your money. Looks like the guy at the dealership is a parts changer and not technician. I tell you what, take your car back up there and tell him to look at the Long Term Fuel Trim and see what reaction you get. If he seems looks at you like "huh"? then he has no idea what he's doing. Next step, find the service manager to ask him why his techs are taking people's money.