check engine light on after headers & tune!
03-06-2008, 10:00 PM
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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?
03-06-2008, 10:02 PM
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03-06-2008, 10:03 PM
#3
Have it turned off?
03-06-2008, 10:43 PM
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its most likely the rear o2 sensors headers make you run rich. It sounds like you have a bad tuner as well. I put headers with no cats and a pro tune and havent had a single problem.
03-07-2008, 06:29 AM
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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
03-07-2008, 02:13 PM
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Did you retighten the header bolts after heat cycling the engine? If not then the are most likely loose allowing outside air into the exhaust stream, which will through a CEL. Cheap fix if thats it.
03-07-2008, 02:34 PM
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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.
03-07-2008, 05:42 PM
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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.
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
03-07-2008, 09:54 PM
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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.
There ya go. This was my exact problem and exact solution.
03-07-2008, 11:44 PM
#10
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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.
03-08-2008, 12:47 AM
#11
Team Owner
03-08-2008, 07:28 AM
#12
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.
03-08-2008, 03:46 PM
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