NoLeaks2001

Hi all. 2001 Grand Marq LS with 28K miles has fumes coming out the vent on the dash and it's been getting worse to the point that I have to make sure it is closed.
My first guess is a loose exhaust mani (but there is no accompanying noise,no ticking or anything) but before I go in there I wanted to check with you guys and see if this is a common thing (real smelly vent air) with a common cause. If not I will read up on torque specs and start checking around. Thanks-Brian-

R.S.LOGAN

Could be heater matrix smell ? Or is it an exhaust or oily smell ?

Bert

It may also be the seal at the rear of the engine compartment that the hood sets against when closed.

__________________
Bert

NoLeaks2001

R.S.Logan; It smells more like exhaust,but then I don't know what the heater matrix is. It smells distictly "unhealthy" as if it was leaking exhaust.
Bert;I will check the seal next time out. That must be the prob.
Thanks. I may re-torque those manis too.

no_common_sens

It's pretty typical for exhaust studs to break off at the backs of the manifolds. They don't often get noisy though. Look for carbon tracks around the rear exhaust ports on the heads. On rare occasion, the EGR tubes can crack, but they generally do get noisy. It's worth looking for carbon tracks at the fitting off the manifold anyway. You'll at least be eliminating it as a variable.

One other thing to investigate would be to look for something burned to your exhaust pipes. We occasionally get a plastic bag of some kind that gets caught to the exhaust, melts, and smells really bad. After a while, your nose can feel kinda dry with that subtle burning/stinging feel as you breathe in really similar to an exhaust leak inside the car. If you find it to be your problem, some quality time with a razor blade scraper and a high speed wire wheel will get your odor problem solved.

We've also had an occasional valve cover leak that has allowed enough seepage to get out and burn on the manifolds. These ones have tended to get through the vents really easy regardless of hood seal.

NoLeaks2001

Thanks n.c.s.
Now with the info from above I should be able to fix this I hope.
I'll post my findings for the record.-Brian-