Question about 1999 Mitsubishi Montero Sport

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Failed smog test due to CEL - second opinion please - not sure I believe mechanic

I just took my 1999 Mitsubishi Montero Sport in for a smog test and he passed me on all but the function. My "Service engine soon" light was on so I don't know why he passed me on the visual. Anyway it brought up 3 error codes: P0161, P0421, P0505. O2 sensor, CAT converter, and idle control system malfunction....whatever those mean. I took it to a mechanic and he reset the conputer and turned off the light with this gadget thingy that he said reset the computer. He told me to drive the car for a couple days and if the light doesn't come back on to have it retested and it will most likely pass. However if the light comes back on it could be $200 for the O2 sensor, at least $800 for the CAT Converter and he could not give me an idea about the last one. Anyone have any idea if this is accurate? FYI all the readings on the smog were well within the range, not even close to a fail and it runs great never a problem.

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I have a 98 Montero Sport and have yet to fail a test. I have changed a CAT Converter for 200 and some O2 sensors for 50 per since i had the car. you can get a aftermarket universal O2 sensor at a good price as for the CAT Converter ya they are expensive I just knew the guy. As for the dash light disconect your battery it will reset it

Posted on Jun 08, 2009


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