View Poll Results: CEL or not? Stock air/fuel or not?
Aftermarket cat, stock A/F, no CEL
11
10.28%
Aftermarket cat, stock A/F CEL
33
30.84%
Aftermarket cat, modified A/F, no CEL
34
31.78%
Aftermarket cat, modified A/F, CEL
29
27.10%
Voters: 107. You may not vote on this poll
Do you have a CEL with cat or not? survey
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Based on our testing, there is over a 1 pt a/f difference with the CEL due to removal of the cat. This is a significant problem, and we would highly recommend not running your car hard with a cat inefficiency cel.
Testing was conducted on 2 different EVO's same day, with multiple dyno pulls. We would essentially run the car until the cel came on, watch the a/f's lean out, reset the ecu, watch the a/f's go back to stock until we hit CEL again, and watch the a/f's lean out. We first stumbled across this problem testing various cat-deletes. Hope this helps.
Cheers,
Gary
Gruppe-S
Testing was conducted on 2 different EVO's same day, with multiple dyno pulls. We would essentially run the car until the cel came on, watch the a/f's lean out, reset the ecu, watch the a/f's go back to stock until we hit CEL again, and watch the a/f's lean out. We first stumbled across this problem testing various cat-deletes. Hope this helps.
Cheers,
Gary
Gruppe-S
i have a buschur racing turbo back with the testpipe with the o2 bung...i was driving tonight and the light goes on (my exhaust had been rattling not too loud since i put it on like 2 days ago)...i slow down and while i idle the rattling is very loud compared to before..did some pipe become disconnected or something because both the CEL and the rattling happened right at once...
Evolving Member
Joined: Nov 2003
Posts: 120
Likes: 0
From: Southern California
any test pipe that promises NO CEL is just going to trick the ecu into not triggering it. It's not making the car run any better.
Of course running catless will trigger a CEL. It drives the O2 sensor nuts.
a test pipe is a test pipe, as long as it's straight through, it's doing the same as every other test pipe out there.
Of course running catless will trigger a CEL. It drives the O2 sensor nuts.
a test pipe is a test pipe, as long as it's straight through, it's doing the same as every other test pipe out there.
Newbie
Joined: Oct 2003
Posts: 76
Likes: 0
From: Pensacola
When I originally replied to this thread I was thinking about buying the BR 3" turboback exhaust. Since then, I have purchased the BR exhaust and installed it. No CEL from the exhaust, but I did get one from an overboost condition due to the intake. Once that is solved, I do not expect to get a CEL at all. The system that I ordered from BR has the test pipe.
I have B&B DP and Catback with UR test pipe. NO CEL!!! It doesn't
Because of the design it actually gets a signal that does not set off the CEL. It's been on my car for about 6k miles and still no CEL!!!
Tofurky...trick the ecu into not triggering it...