P0430 Lexus -

Question

My 1995 Lexus LS400 passes emission tests with no problem, but the check engine light comes on again after driving about 100 miles. been doing this for a couple of years. Car runs great. Good mileage. I've been told that if the converter was bad it would not pass emission tests. Mechanic said that if it's passing the emission tests nothing needs to be done. I want to know what could be causing the check engine to come on given it passes the emission test.

Thanks

Answer 1

Hi there,

I would look at the rear O2 sensor as a possible issue. If it's not working properly and generating the correct voltage after the converter cleans the exhaust, it will give you a code saying the converter is no good.