Check engine

Asked by Sep 13, 2017 at 12:36 AM about the 1999 Lexus LS 400 RWD

Question type: Maintenance & Repair

My check engine light came in for a day... then off.  
About a week later it came on again for a couple
days and went off.

I got it check at Autozone and it was code P0430
catalyst system efficiency, Bank 2.

What should I do even though it went off? Am I
good? Do I need to replace something?

Trying to conserve $.

2 Answers


P0430 can be a serious repair if the catalytic converter has failed. These parts are often expensive as they contain rare earth metals. Once the P0430 code is found the vehicle should be repaired ASAP to avoid damage to the catalytic converter. Since it is currently intermittent it could be an easy fix but if you let it continue then it can damage the catalytic converter which will cost you a lot of money. Below are is what is commonly done to actually diagnose what is wrong. This code can be hard to fully diagnose without the proper tools. •Installs the scan tool to the vehicle's DLC port and check for any codes present •Notes freeze frame data for every code found, this indicates the vehicle's conditions at the time the code was set •Clears all of the codes present •Performs a road test under similar conditions to the freeze frame data to confirm the problem •Performs a visual inspection of the exhaust system •Checks for any exhaust leaks •Uses a scan tool to monitor the oxygen sensor data and checks for proper operation


Look for vacuum leaks.

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