Exhaust leak in the cabin ?

[D Seattle]

 Sometimes bringing an old thread it back to life is not a bad thing. I have been having the exact same problem with my car and assumed I had an exhaust leak under the car. I will spend the weekend working on the seal and latch, as well as sealing holes between trunk and compartment. Thanks for the flashback. 

[Tommy]

Thanks Simeon, I couldn't find that one. I was just a bit unsure because I have replaced all the panels around the trunk so I'm not 100% sure about their shape and alignment but it seems the seal is the culprit after all.

[dbmw2002]

Yes the trunk can leak fume, but how are they getting into the cabin? Check the bulkheads fit in the trunk and if a sunroof car the round vents above the  wheel arches in the trunk. Factory installed foam but I sealed mine with shaker can lids, much better.

Seal the heater phenum properly and u should be good. 

[D Seattle]

 

Another idea: some of that expanding spray foam.  It expands to fill any space and if you get the right kind will form a seal.