Fumes in cabin CLK430

[balruddery]

Ever since having had instrument cluster pulled to replace bulbs I've had fumes in cabin. Is it possible gromett around speedo cable has been misplaced? I've asked stealer who did work and he says definitey no but he would wouldn't he. Any ideas please. Fumes are like crankcase fumes.

 

[Sp!ke]

If your crankcase breather is properly attached to the airfilter box then I'm not sure what fumes there would be coming from the engine.

More likely to be a leak somewhere along the length of the exhaust getting into the cabin somewhere, maybe through the transmission tunnel or through the vents in the boot.

If you cover the exhaust briefly does it sound/feel like there is a leak in the system?