Hello all,

The heater on my e34 is acting a bit strange. After running the heater a few minutes, I get this weird coolant like smell. It usually goes away on its on after a few minutes. However, occasionally if the heater has been running for a long time the coolant smell gets a lot stronger and I can see some smoke (or gas) in the cockpit that comes from the vents. What could be causing this (hoses, heater core, coolant)? Any advice is appreciated.

Thanks

sounds just like a heater core problem..although check to see how your heater control valve is in the engine bay (its the weird black box on the side of the drivers strut tower w/ two sensors attatched to it, you will see heater hoses also, check the clamps...mine was leaking slightly and caused a coolant smell which i thought for sure was the heater core

got to do this one on two different cars this winter.
pulled everything in preparation to change the heater core but found the piping to the heater ( the line from the fire wall to inside the car) had been cracked. both were cracked at the inlet pipe o-ring neck. this piece isn't as hard to replace as the whole core and you don't have to tear as much off. do check everything at the control valve and aux pump first. the pumps will leak where they bolt together also.