[Dave at Pelican Parts]

Usually smoke and stink in the cabin when you turn on the heater is caused by oil that has dripped onto the heat exchangers. (It seems like you can have a leak at the front of the car and it will still find a way to drip on the heat exchangers...)

Actual exhaust leaks are much less common--but are much worse for you, because you often cannot smell or see them. You may be able to use a household CO alarm to see if you're getting carbon monoxide in the cabin. If so, then it is very likely that the exhaust pipes are indeed leaking into the heat exchanger part. As noted, this is Very Very Bad--possibly fatal.


The heater blower fan is run by the rear-most relay on the relay board. The relay is triggered by the lever on the center tunnel--this lever grounds the wire that runs to it, which is what triggers the relay to close. The Infamous Seatbelt Interlock Relay doesn't have anything to do with it, I don't think.

The Relay has only one real function, to keep the starter from working sometimes. Permanently join the two fat yellow wires (one may have a red stripe) together and it should be disarmed. There are other wires going to it, but they don't do anything once the relay is unplugged.

Ugh, that's not quite precise, but I'm having trouble expressing my thoughts. Some of the wires carry power to the relay connector, and another wire is crimped into that connector as well. The second wire carries the power to something else. If you cut off the connector, you have to splice those two wires together to make sure the "something else" still works. I hope that is clear.

--DD