My '92 Loyale emitts an exhaust smell whenever the heater motor is blowing. I've tried searching other threads but have found nothing similar; and she doesn't have a cabin air filter. I'm lost on where to look next.

Maybe you have an exhaust leak.

rusty rear quarters plus windows down equals exhaust in the cabin. windows up and fan on should keep it away.

 

maybe you have a leak on the y pipe flange?

Also, check that the rubber seal around the hatch-lid is not leaking. Exaust can come in through there.

I don't smell it unless the fan is blowing. The smell is as strong as the blower speed. (More air =stronger smell) No open windows, and hatch seal looks good. Plus, the exhaust sounds good, no audible leaks. I won't have a chance to inspect it until tomorrow.

Edited December 1, 201114 yr by Bobaloui

there is a rubber drain tube near the cat and the egr side of the firewall for the air conditioning. maybe the exhaust is coming form there?

Crack a window open a little bit and remind yourself; "This is a 20+ year old car" =P

crack a window open a little bit and remind yourself; "this is a 20+ year old car" =p

 

If you have an exhaust leak up front, it could be coming in through the plenum's intake (which, I believe, is right under the windshield). Although, typically, you would notice an exhaust leak, pre-cat, by sound alone. Does it do it on all settings (defrost, heat, a/c...)? Does it only do it on heat, or does it matter what temp setting it is on? If your car has a/c, put it on a/c max (just the button, not the temp setting), and see if the smell persists. This should cause it to start recirculating the air in the car, rather than pulling (fresh) air from outside.