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YOUR RESEARCHCat bypass pipes??..someone please give me some insight!!
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Replace cc
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Suggestion
Although many cc bypasses have a place to insert the 02 sensor, they still don't look much like the regular cc, so you may need to replace the cc to pass annual inspection.
Cat bypass pipes??..someone please give me some insight!!
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Leading evidence: 'Replace cc' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Replace cc' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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Replace cc
No successful repair reported for this finding.
0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion
Although many cc bypasses have a place to insert the 02 sensor, they still don't look much like the regular cc, so you may need to replace the cc to pass annual inspection.
Cat bypass pipes??..someone please give me some insight!!
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Counts describe captured discussions, not unique people or a diagnosis. Author identities are not reliably stored. Exact duplicate evidence is counted once across matching discussions; one discussion counts at most once per action/state. Multiple repairs reported together remain a combination. Suggestions and failed attempts do not establish a fix. Matches cover whole discussions and can include related faults, model variants and incomplete threads.
9 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
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Whate are the implications of cat bypass pipes?
I don't care about emissions. (we have no such enforcement in MI)
I have Fabspeeds, but an otherwise stock motor.
Bypass pipes can be made by a local shop with O2 sensors in place.
No info is available through searching the archives...
Thanks everyone!
P1CR,
As I mentioned in another thread, Wilber on this board has a downpipe for the 996 that is a straight bolt on, and you can fit the O2 sensors on it with no problem.
He just did a C4S last weekend and a friend installed one on his Boxster S.
MI doesn't have emissions checks? Does MI have annual inspections? My area doesn't measure emissions, but does have a visual inspection to insure that a catalytic converter (cc) is at least in place. Although many cc bypasses have a place to insert the 02 sensor, they still don't look much like the regular cc, so you may need to replace the cc to pass annual inspection.
from what i read cel will light when something is removed. they (sensors) know a temp difference when something, ie. cat is missing.
however a spacer can be built to move the o2 sensor back and hold heat. oro you can buy 'em for like $200
bypass pipes with 02 sensors don't pass inspection and make no sense anyways........ try low restriction high flow, however you will lose torque, gain hp. Mine on the black aero, were 200 cell, nice, loud, light, but torque was sacrificed. My aero had headers to highflow cats to open exhaust, very raspy, very loud, but cool!! The car also had ducted air intake and ecu mods. Great car!
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