smell exhaust fumes

[kerry]

I notice when I put my landing gear down coming into the pattern I smell a hint of exhaust fumes.  Nothing ever shows up on my CO indicators and I can't find and cracks in the exhust system.  I took a look at other M20's around the airport and have noticed a lot differn't configuration of tail pipes (bends, lenghts and distance from the gear door).  My tail pipe is about an 1" or so from the gear door and the gear door does get coated pretty heavy with gray ehaust.  My first thinking would be to reconfigure my tail pipe, but I thought I'd get some input from this forum.

[Piloto]

When properly aligned there should be no exhaust stains on the gear door. The exit of the exhaust pipe should be 45 deg away from the door. When the nose gear door is open it creates a vacuum that can suck the exhaust gases. Check that the seals on the nose wheel well are in place.

José