MY 92 Camaro RS 305, Is getting new headers as we speak, the ond ones were shot. I also know that my cat converter has issues too, as I hear a leak from that spot, it rattles because the heat shield is broken, and my check engine light keeps appearing for o2 issues. I have the tools and would like to just cut it off and replace it with a straight pipe. I hear rumors however, that doing this would make the car run bad because of another sensor and that I would have to get the computer on the car re programed?!? Does anyone know if this is true? Will I REALLY have alot of issues from cutting the cat off other than the check engine light being on or is this a fib? Thanks
-Craig

 

You'll have NO issues at all if you remove the cat. It won't set off a check engine light, nor will it make the engine run bad. Your car doesn't have a post-cat oxy sensor (starting with OBDII), so your computer doesn't even know if it's there or not. Even if you did have a post-cat sensor, removing it wouldn't affect the engine, you would only get the pesky check engine light. The sensor is there to diagnose proper operation of the cat, not the engine. But that's not an issue for you. The only issue is if your car still needs to get emissions tested, then it will fail the "visual" portion of the test.

 

Maybe I'm wrong and I don't want to start anything with camaro69 as he's helped me out before; but won't the removal of the manifolds back and replacement with headers/straight pipes delete the o2 sensor, causing an open loop FI scenario?

 

+1
i have a 95 chevy blazer that is obdII compliant with a post cat O2. i cut off my cat and straight piped it and it never threw a code

 

Oh, and I see you're from jersey...aren't most of the counties pretty strict on emission laws?

 

I thought OBDII was from 96 on.

 

yes, but that was when it was required to start. some vehicles were compliant to obdII well before it was required. some models started late 80s and early 90's, some didnt start until 96

 

They are however i have my own ways of getting an inspection sticker. I pay a guy who owns a shop to hook me up. Whats this about a looping FI scenario?

 

When the OP was referring to his cat and said "I have the tools and would like to just cut it off and replace it with a straight pipe. I hear rumors however, that doing this would make the car run bad because of another sensor...
I read that as him referring to it having a post-cat sensor, which he doesn't. Of course you need to retain the main oxy sensors in the exhaust manifolds/headers, so the engine management system can adjust the air/fuel mix correctly.
Craig, basically open loop is the preset setting in the computer that controls the air/fuel mix when the engine is cold. It gives the engine a richer fuel mix to make the car more driveable with a cold engine, much like what the choke does in an old carbureted engine. After the engine warms up, the system goes into closed loop and sensors take over and tell the computer to make air/fuel adjustments accordingly.

 

I read that as if he was installing new headers, or replacing old ones....Rarely in my experiences are people replacing headers and drilling/tapping 02 sensor threads. Since he mentioned skirting emissions, I'd also assume non smog headers leaving no "bung" to tap through....


I'm setting myself up for some fatherly advice on "assuming" aren't I?