87 5.0 - Exhaust in cab..help!


New Member
Oct 9, 2004
I have an 87 mustang LX 5.0 conversion that is gettin exhaust in the cab. I checked the pipes for leaks, but I am not getting any leaks at the headers, the H-pipe, the cats, the mufflers or at the tailpipes.

It has a new Flowmaster cat-back on it.

I replaced the weather strips on the hatch and the two doors (since the original ones were torn to shreds) and I am still getting exhaust in the cab.

Has anyone else had this problem?

Are there any other intrusion points on the undercarriage where exhaust could be getting in? :shrug:

It's driving me nuts and I almost passed out on the road the other day from the fumes.

Any help would be appreciated!
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Unless you have some rotted pipes the most likely place for leaks is going to be at your 4 socket/ball connections at either end of the h-pipe. Usually you can tell a leak by the telltale black soot around the leak. If you just put a catback on you may not be able to tell that easy if there is a leak unless it is cold out and you can see the exhaust. If you nail the throttle and is sounds like an old chevy truck then there probably is a leak somewhere. If you can smell it while your driving then you definately have a leak. Normally you only smell it when you are idling and the exhaust can linger and filter up through the car. I would check for any cracks in your floorpan, missing bolts, and your seals around the e-brake cable and shifter housing.