2002 Lexus Es300 - 165,423 Miles.
Bought this car for $3000 with 156k miles. Just got Error Code P0420 while driving on freeway. Car is still driving fine, no hesitation or misfiring. What can I do? New Cat? I’m not sure which Cat it is either. Is this going to be an expensive fix? I could replace cats myself if i have to, but if it gets to that point maybe it’s time i sell the car?
First make sure you do not have any leak in the exhaust system. Check the oxygen sensor and make sure it is functioning correctly. If it is confirmed that the catalytic converter is bad, the OEM ones are very expensive, you may consider generic one.
the weird part is it came on about 2000 miles ago while passing gallup new mexico and i reset it and it didn’t comeback. +2000 miles later i’m passing through phoenix az and it popped back up.
Sometimes the gasoline affects the catalytic converter. That's why Scotty says to clear the code and put a premium Shell gas to see if the code comes back. Also check out this video (if you have not seen yet):
https://www.youtube.com/watch?v=qJTmddbOxMk
Thanks for sending that. I’ll definitely have it checked out. If it’s beginning to look like they’re getting clogged, then i’ll definitely sell the car. I was gonna say, funny enough, right after i cleared the code i happened to be next door to a shell and got a full tank of premium. I’ve driven 180 miles and no check engine has comeback yet. What could that mean?
First you should make sure that the modules are ready. If so, there is a possibility that you have carbon built up engine that runs better with higher octane gas. That's a possibility though.
i’m confused, i thought lexus es300s all used premium 91 gas? i know the manual recommends it
What do you expect from a nearly 20 year old car? Yes, this is going to be an expensive fix. They run about $1000 each at Autozone. Two required.
I heard that it’s 3 converters? a downstream and 2 warm ups?
It does, but the down stream pair come together in a replacement unit. Just go to the Autozone website and check them out.
Will do thanks.