open hood... look on the exhaust manifold, 2nd cylinder back from the front... there is a small bellows that ALWAYS cracks... it will limit turbo boost pressure also.

another possibility is downstream of the turbo is a flex connector in the main exhaust pipe... they break as well. either one would dump exhaust into the engine compartment and allow it to pull into the heater intake vent.

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 560SL convertible
1987 190D 2.5-5SPEED!!!

1987 300TD
2005 Dodge Sprinter 2500 158"WB
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!