Exhaust Smell in Cabin when Heat is On
I have a 2006 ZX4 and for about a week and a half now I've noticed that when I'm sitting idling at a stop light and I have my heat on, I get a very strong, bad smell like something is leaking or maybe exhaust in the cabin of the car. I have started turning off the heat when I come to stoplights and also cracking the window just to be on the safe side, but I"m concerned about what could be causing this problem. I'm taking my car to someone on Saturday and wanted to have some ideas about what could be causing the problem when I talk to him. Has anyone experienced this? Do you have an idea what could be causing this problem?