951blur

So for the past month I have been trying to get the exhaust / engine fuel smell from coming inside the car. The smell would not only make me feel sick and cough but it would soak my clothes in a horrible stench. So in order to remove this problem I replaced the hood seal, I replaced the hatch seal this decreased the problem by about 50%. I pick these up from Kyle with only944.com.
Once those were fixed I could smell fumes coming from the shifter and hot air was blowing on my hand and I realize there was no rubber shift boot sealing the shifter. Some of you are probably wondering how that was possible well when I bought the car it came with a Momo shift **** and a Lindsey racing short shifter. So I put the rubber boot in and new oem style shifter, shift **** and boot that helped by about 25% and the last thing that really helped dramatically was the tail light seals I picked up from 944 online. These were by far the cheapest out of all of those, but not only is the car quieter at highway speeds there is 0 exhaust fumes coming into the car now. Wife is happy

shortyboy

if you were smelling exhaust fumes in the cabin it would indicate there was a leak in the exhaust system in the engine bay. I had some leaks in my header gaskets which caused the same symptoms as yours. I would check for any leaks in the headers / x-over pipe / wastegate pipe those are notorious for leaks or cracks.

951blur

Yeah a couple of the donuts that were in the crossover pipes and the exhaust below needed to be replaced and I did that when we were putting the engine back in. But so far no header leaks or crossover leaks.

KVDR

I have similar experience - the hatch and firewall hood seals each helped. Shift boot checks out.

I just need to replace the tail-light seals (have parts) and I'm expecting that to solve this once and for all.

Jay Wellwood

Great information - thanks for sharing your experience.

951blur

Yeah no problem guys. Glad this is behind me. Now that I can enjoy the car. I dialed in the M-Tune today 11.7 at full boost. First 3 gears are useless!