Solved!!!! Fumes in interior

My convertible had a fume problem for first two years of ownership when the top was up and any window was cracked open. I changed the trunk seal with no effect. I did find if the heater/vent fan was on, windows up; no fumes.

Here is what I discovered:
A low air pressure area develops in the car when a window is cracked open. This causes any exhaust gasses circulating in turbulence created by terminus of trunk lid to be sucked into the body shell; this is more prevalent with a rag top as trunk to passenger compartment is less segregated than a sedan. My car has duel pipes with 340 rectangular exhaust tips that dump their combustion products at the bottom of the rear bumper where they swirl around in a low pressure area at the end of the car, and don’t get forced into air stream as quickly as a stock stile down turned pipe would.



I discovered after replacing all the gaskets sealing the tail lights, and repairing a cracked lens that almost all exhaust fume entry to cockpit was stopped. One could tape over the vent holes located in lower trunk lid lip, and probably stop all fume entry. Another test would be to crawl into trunk, and have friend shine a light around all trunk lid’s contact area with body to locate any gaps, and seal those up.

If you are getting engine compartment fumes, gasoline, oily smell, etc, replace all the firewall gaskets.

All these correct original stile new gaskets are available from Detroit Muscle by the each, or in full sets.