Question about 2003 Mitsubishi Lancer

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My check engine light will not allow my car to get inspected. when I plug the computer in it says that it is a O2/cat failure. I have with in the last 10 days have had both cats replaced as well as both O2's replaced and im still getting the same reading. But when I plug it in everything is reading correctly both O2 sensors are reading in the range that they are suppose to. does anyone have any ideas on what could be going on?

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  • lee_damiani Jul 21, 2009

    the codes have been cleared and they kept coming back on, but i believe that i have solved the problem, there is a tsb on the code and it requires a software update

  • lee_damiani Jul 21, 2009

    they have been cleared and they kept coming back on, i believe that i have fond the problem thugh. there is a tsb on the code that keeps coming up. so its a software fix in the cars cpu. the light is sending out the wrong error message



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Codes will need to be cleared they will not go out on their own then a readiness drive will need to be performed dealership should be able to tell you how to perform this step

Posted on Jul 21, 2009

  • paul campbell Jul 21, 2009

    software could definately be it



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Just changed original cats with direct fit magnaflow

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If you have emissions testing or regulations to that effect where you live, you will not pass inspection. In addition, if you have smog laws that mandate cats and other smog equipment, you could be risking a huge fine if you're found to have removed them. I'd check with an auto parts store about getting some generic universal cats (make your choice based on the length of the cat assembly and the diameter of the inlet and outlet pipes). These are generally far less expensive and work just fine.

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