helppp
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Joined: Jan 2014
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From: rochester ny
helppp So i need to get my car inspected. Problem is....my downpipe has a hiflow cat on it. Which triggers my CEL to come one. I can turn the cel off with my tuner, but after only 20 miles or so of driving the cel comes back on. Even if i turn off the cel right before inspection, it still wont pass the bc it takes longer driving for the system to pass the "readiness". Any clue how the hell i can somehow fix this?
I am kind of confused as to the way your question reads, I am assuming that by downpipe you mean the exhaust pipe, (normally a downpipe is in regards to a turbo setup) and I am assuming that when you turn it off with your tuner you mean a code reader. If I am wrong, please let me know, if you have a tuner hopefully you would know how to solve this problem. If I am correct in my assumptions read on,,,
Erasing the fault will not help, as you have seen. The ECM is scanning and when the inspection scans the ODB system it will flag. If you are throwing a code due to a high flow cat that tells me that your ecm is still using the reference from the rear O2 sensors, that differential is what is throwing the code. You can do two things, there is a rear o2 simulator that can be used, http://www.ws6project.com/user_stor/...or-simulators/
Or you will need to have the rear o2s deleted from the ECM that way it never looks for it, and you wont have this problem anymore. This is usually one of the first mods people do, a simple mail in tune can take care of it, or if you know any tuners they can do it.
Erasing the fault will not help, as you have seen. The ECM is scanning and when the inspection scans the ODB system it will flag. If you are throwing a code due to a high flow cat that tells me that your ecm is still using the reference from the rear O2 sensors, that differential is what is throwing the code. You can do two things, there is a rear o2 simulator that can be used, http://www.ws6project.com/user_stor/...or-simulators/
Or you will need to have the rear o2s deleted from the ECM that way it never looks for it, and you wont have this problem anymore. This is usually one of the first mods people do, a simple mail in tune can take care of it, or if you know any tuners they can do it.
Last edited by RARON455; Jan 20, 2014 at 10:12 AM.
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Joined: Sep 2005
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From: Bucks County, Pa.
The stock (or stock like aftermarket ones) catcons are basically downpipes in that they connect the stock iron manifolds to the y-pipe. 
Most of you with non-catted longtubes seem to forget that this is the way these cars are setup from the factory because you've had non-stock setups for so long (or NEVER).
Most of you with non-catted longtubes seem to forget that this is the way these cars are setup from the factory because you've had non-stock setups for so long (or NEVER).
