I have a 98 Intrepid that I purchased in February of this yr. So far I have changed all four of my O2 sensors (might have changed 2 twice!) but I still get the same codes for the Check engine light. The last sensor was changed in August and now the light is back on with 420 and 432 codes. Someone told me it might be my fuel injectors or misfiring(?). I dnt believe my spark plugs was changed during my tune up in March. Pls help, dnt want to get two new converters at 150 each! what should I do besides keep changing O2s

 

NOTE SURE WHAT YOU DID, BUT THAT WAS THE START OF MY PROBLEMS, I HAD THE SAME CODES, HAD TO REPLACE THE CV'S THERE IS 2 OF THEM, AND IT COST ME $1000.00. WHAT HAPPENED TO YOUR CAR? THANKS PH

 

Sounds like a bad catalytic converters bank 1 and 2 flagged.(btw note to 1998 intrepid, when most people say cv's, they mean constant velocity joints (also 2 in a car) and I think you may confuse people if you say cv's when talking about catalytic converters). How many miles on the car? Normal vechicle miles or engine misfire can cause them to decay. Of course the O2 sensors do play a role in the detection of the cat. going bad and therefore can misdiagnose the code. More than likley this is not the case with you asyou have already changed them and normaly when an O2 sensor goes bad, the computer can figure its the sensor by the resistance. There is still a slight chance the O2 sensors you put in failed in such a manner that it's not flagging correctly. You could try to swap the downstream left and right, then see what happens. If nothing, swap the upstream left and right,lastswap the left up with the left down, if nothing changesodds are a bad cat(s). Then there is also a small chance the O2 wire are broken and shorted with just the right amount of resistance that the computer thinks they are fine (not likley to happen on both banks) or a chance of a bad computer. Ods are bad cat(s).