[maclaren65]

Ever since I added the Steve Wong chip and cat bypass pipe (which I love!) to my 87 3.2 Carrera, I've noticed that when I use heat in my car I get some exhaust fumes. Enough that I usually crack my windows open regularly when I use heat. I didn't notice this situation when my cat was connected to my exhaust system, which makes me wonder why this is happening now and if it is related to the cat bypass. Do you think my factory heat exchangers might be leaking?

Thanks,

Richard