Help, 85 300TD fluttering air noise
 

New member here,

1985 300TD Wagon ~220K miles, owned for over 3 years, no major problems with exception to replacing the alternator

This morning on my way to work I turned on the heater and with it came a fluttering air noise that cycles with the rpms. Turned off the heater, still there. Turned the car off and on again and it is still there. It seems to be in sync with the engine. The faster I go, the faster it pulses. It is slow during idle. I think it may be an exhaust leak? Maybe something with the turbo or air intake? I can hear it inside and out of the car and can sometimes smell exhaust but not too often, I closed the vents just to be safe.

Haven't had time to poke around with it since I am at work now. Just curious to see if anyone had any ideas.

Thanks,
Mike

I've had similar noises that came from using a straight hose, instead of the cigar hose, for the fuel return from the top of the fuel filter to the return line to the tank. Do you happen to have a straight hose for this hose? Also try watching that hose and see if you can see it pulsing. It may have swelled inside and cause restriction. The proper hose it supposed to be skinny at the ends and fat in the middle. Like the pic below. Most cars it doesn't seem to make any difference if you use a straight hose, but on occasion it will cause pulsing sounds.

http://www.pelicanparts.com/catalog/...0089976482.jpg