Fabspeed Cat bypass, HELP!!!!!
#1
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Fabspeed Cat bypass, HELP!!!!!
What happens to the two before cat ox. sensors? Fabspeed said keep them plugged in, but zip tie them out of the way.
Anyone with a 96 and up cat bypass?
Anyone with a 96 and up cat bypass?
#2
Hi HK, I have straight pipes. I did zip tie the secondary O2 sensors even though they are dissabled (you need to program the ECU for that, otherwise, you'll have a CEL). You need to use the primary sensors though, the ones right after the headers. Don't mix them up if not your car will not idle properly and you'll lose power.
#3
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I put bypass pipes on my 97 993 last spring. I put the primary O2 sensors in, and the secondary zip tied out of the way. In about 100 KM my CEL came on, I had my dealer turn it off but it came back on sometime later last summer and stayed on. This spring when I got it out from winter storage the CEL was off and it stayed off for the 1000km I drove it before trading in...
#4
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I was wondering if by disconnecting the two after the CAT O2 sensors anything is affected in the way of performance. I understand a check engine light will illuminate. But I was thinking that after CAT sensor does not do anything to alter the computer.
On another of my OBD2 vehicles nothing is affected by way of perfomance. The after CAT 02 sensors just indicates the CAT is functioning as intended.
On another of my OBD2 vehicles nothing is affected by way of perfomance. The after CAT 02 sensors just indicates the CAT is functioning as intended.
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Ron, from my experience you must have the sensors functioning unless you have your ECU programmed. When for some reason my O2 sensor was disconnected, I had all shorts of problems with throttle response. The car would hesitate, especially if I was partial on throttle like it had a turbo or something. It was annoying as hell especially on a race car. My mechanic checked everything and realized that the O2 sensor ( 1 on my 95) was disconnected... When it was connected the problem went away.
#6
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Thanks for all the replies. I guess I will leave the secondary O2 sensors plugged in but zip tied out of the way, this way they continue to read O2 as they should. The primary o2s are important because they regulate air/fuel mixture, if I understand it correctly. I guess I will see how it performs.
#7
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I am about to pull the trigger and purchase a CatBypass to compliment the Fabspeed Mufflers I installed recently.
If I zip tie secondary O2 Sensors which were mounted in the cat I remove, where and who could program the Emmisions Control Unit? I am assuming a dealer would not want to mess with that.
Ron, from my experience you must have the sensors functioning unless you have your ECU programmed.