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New member, please help. 89 gt new exhaust running rich.

887 Views 6 Replies 4 Participants Last post by  Smurf stang
i have an 89 gt with a few slight mods. it has a cam, cold air intake, msd coil, 3 row radiator, and an electric fan. this past week I had my new exhaust put on. it consists of mac 1 5/8" long tubes, 3" catless h pipe, and 3" cat back. Before the exhaust was put on, the car ran perfect. after the exhaust, the car ran rich. I was able to smell fumes when I was idling and sometimes when I drive. one of my buddies recommended swapping the 02 sensors for heated 02 sensors. he said that the 02 sensors required a specific amount of heat from the engine that got reduced when the long tubes got put in. need some help. any recommendations?
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Well if it ran fine before then something happened with the install. Maybe something wasn't connected, broken or anything.

I would run the codes first off.

Secondly I would give the car a good once over visually and check it all out.

What is the timing set at?
What is fp set at?

Now with a freer flowing system you will be able to smell some fumes tho.
Run your codes. See what pops up. Plus it is free.

The problem is not the location of the O2 sensors.

There are also no magic answers for certain problems as it could be 100 things wrong. Start simple and free then go from there.
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