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O2 Sensors response to no Cats?

Someone please help me understand this. If I remove the vertical cats closest to the headers and replace them with a straight pipe will the car run fine?

As I understand posts I have read, it seems warning lights will light up on the dash but the car will still run normal. Is that correct? Will the Track Key functions still work? Furthermore, will the results be the same with long tube headers?

If I reinstall the vertical cats will the warning lights shut off or will I have to take the car to the dealer to have them turned off?
 
seca954 said:
Someone please help me understand this. If I remove the vertical cats closest to the headers and replace them with a straight pipe will the car run fine?

As I understand posts I have read, it seems warning lights will light up on the dash but the car will still run normal. Is that correct? Will the Track Key functions still work? Furthermore, will the results be the same with long tube headers?

If I reinstall the vertical cats will the warning lights shut off or will I have to take the car to the dealer to have them turned off?

If you replace the factory cats (there are only 2 and they are closest to the factory headers) with a straight pipe (or for that matter, hi-flow cats), you will get a CEL with a P0420 and P0430 cat efficiency codes. The car should still run fairly normal. Track Key will function as normal. Use of long tube headers will end with those exact same results. Once you re-install the factory cats, you would clear the codes (CEL) with a scan tool and perform a drive cycle to get the CAT monitor to set to "ready" and you will no longer get a CEL. This does not have to be performed at the dealer.
 
ArizonaGT said:
What does "fairly normal" mean?
That's not an engineering term? :D
 

ArizonaBOSS

Because racecar.
Moderator
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Arizona, USA
You should not remove them it will not run right the o2 sensor help with fuel/air management and are calibrated for those cats so you would just make it run worse. I do not know if these computers can be tuned to fix that issue or not I do know some of the older cars were able to get away with a tune to fix it.
 

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