diesel odor bad in bedroom

[spopoff]

I have a diesel exhaust odor problem mainly in rear bedroom of coach. I tried to put a halogen light inside engine compartment at night and look for any signs of light around bed and walls, didn't see any. It seems to be at its worst after going down a long hill using the pacbrake, I checked all the exhaust system for leaks ,everything looks good,no soot on connections or manifold. I am up against the wall with this problem. Any suggestions would be much appreciated. thanks Sid

[Gary RVRoamer]

Maybe the exhaust brake itself is leaking, when it engages? You mightn't be able to see that except actually when using it.

[spopoff]

That could be,what part of pacbrake should I be checking for leaks.I just put new flanges on both ends of the pac,plus new c v band clamps ,the exhaust system is new from turbo to the tail pipe. the exhaust exits out the side of the end of the back bumper. I should mention the rv is a 89 sportscoach the pacbrake is the early model.