MIL trouble code 0420, real or false?

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Thread: MIL trouble code 0420, real or false?

  1. #1
    Junior Member
    Join Date
    Mar 2010

    MIL trouble code 0420, real or false?

    This is my first time to own an import car --- 2002 Acura RSX and it has been a nightmare since I purchased it 10/2009. First mistake was buying this particular car in the first place. Just wondering if the trouble codes I have gotten were false codes and the PCM needs to be flash reprogrammed. I am female so what I know is just what I have researched. Here are the chain of events:

    1. "D" drive light blinking on my way home from purchasing the car.
    Took it to three mechanics, two were specialized in transmissions and all said the transmission had internal problems so transmission was rebuilt 11/2009.

    2. Couple days later after completing drive cycle, took it to get inspected and passed. Couple of more days passed and MIL light came on regarding air/fuel mixture too lean. Realized the guy who sold me the car had the wrong air fuel sensor, should have been for a base model not type S, so got the correct one and put it on (Denso). Few days later MIL light appeared again with only the DTC code 0420 catalyst operating below threshhold. Original converter was replaced with aftermarket Davico direct fit converter. 1/2010.

    3. Two whole months go by and no MILs until yesterday 3/25/10. The P0420 is back and just as last time there are no driveability issues. Code was cleared and mechanic said to bring it back if and when the MIL comes back. The converter is still under warranty.

    Could the PCM need to be flash reprogrammed? Here is something else interesting to consider: both times the MIL came on for the emissions issues it was preceeded by the "side airbag off" light coming on for about 5 to 10 minutes.

    Hoping to find a remedy to stop the MIL. Your input will be greatly appreciated.

  2. #1
    Honda S2000




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