Have it turned off?
check engine light on after headers & tune!
Thread Starter
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Joined: May 2007
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From: Houston Texas
check engine light on after headers & tune!
24 hours after new headers and tune (done by vendor), my check engine light has come on. I'm sure its related to emissions. Any advice on what I should do?
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From: Lakewood Ranch, FL
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From: Midland Texas
St. Jude Donor '09-'11
First step, determine what the code is that was triggered. Next step, fix the problem. Could be anything from the wiring got overheated or disconnected to the sensors warming up too slowly.
Joe
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I am sure it is the 0420 and 0430 codes, it is caused by the location of the cats compared to the original ones. In layman terms the reference the rear O2 sensor is looking for is a little different with the cats not running as hot as the factory unit because of the location, so not it will set off you light assuming the factory cat is bad. You cannot change the perimeters of what the VCM is looking for so the only thing that can be done is to turn the light off and flag the VCM not to illuminate the check engine light on that code.
Racer
Joined: Aug 2006
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From: Orlando Florida
I am sure it is the 0420 and 0430 codes, it is caused by the location of the cats compared to the original ones. In layman terms the reference the rear O2 sensor is looking for is a little different with the cats not running as hot as the factory unit because of the location, so not it will set off you light assuming the factory cat is bad. You cannot change the perimeters of what the VCM is looking for so the only thing that can be done is to turn the light off and flag the VCM not to illuminate the check engine light on that code.
Get yourself a scan gauge tool, (not expensive) it will tell you the codes which will very likely be dirver and passenger side, rear o2 sensors, - the gauge will allow you to clear the codes, thus turning off the Check eng light , no problem-
Good luck
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Verdad Gallardo
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From: Falls Church Virginia
I am sure it is the 0420 and 0430 codes, it is caused by the location of the cats compared to the original ones. In layman terms the reference the rear O2 sensor is looking for is a little different with the cats not running as hot as the factory unit because of the location, so not it will set off you light assuming the factory cat is bad. You cannot change the perimeters of what the VCM is looking for so the only thing that can be done is to turn the light off and flag the VCM not to illuminate the check engine light on that code.
There ya go. This was my exact problem and exact solution.
Thread Starter
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Joined: May 2007
Posts: 83
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From: Houston Texas
I am sure it is the 0420 and 0430 codes, it is caused by the location of the cats compared to the original ones. In layman terms the reference the rear O2 sensor is looking for is a little different with the cats not running as hot as the factory unit because of the location, so not it will set off you light assuming the factory cat is bad. You cannot change the perimeters of what the VCM is looking for so the only thing that can be done is to turn the light off and flag the VCM not to illuminate the check engine light on that code.
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St. Jude Donor '03 through '17
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The ECM may throw a cel for the first 100 miles or so, until it recalculates. You can erase the code and turn off the light by disconnecting the battery for a few minutes. If it continues to throw a code after 100 miles, return it to your tuner. Good luck.
