w140 exhaust fumes in cabin!!!
 

PLEASE ADVISE!!! Recently had a major tuneup (wires, plugs, caps, rotors, fuel & air filter); and either prior to, or soon after that I started to smell heavy exhaust fumes in the cabin and trunk.

I took the car to two (2) muffler shops and both stated that they could not detect any leaks. However, I'm still smelling the fumes.

I'm at my witts end.



Any suggestion :confused:

I have a 600SEL W140 and get oil fumes in the cabin as well. I am told it is a leaking roscker cover gasket. Am about to put it in for service.
Hope that helps.

Is the a tapping sound like a bad lifter? If so, you could have a leak at the exhaust manifold.

Clogged cat?

Thanks Vince and Warren.

I do hear a ticking sound sometimes. What are the symptoms of a bad cat???

cat excrement on your bed and scratches on the sofa corners...




sorry.... :D

Still looking for possible solutions!!! Again; according to three (3) mufflers shops, I do not have any leaks.

My father had a mid 80's Olds and he complained about exhaust fumes in the car. He even taped over the interior vents. I was over at his place and he complained about it to me. I could hear the tapping sound and told him, exhaust manifold gaskets. He took it to several shops, they said: lifters.

I told him the gaskets were bad and leaking, evidenced by the fumes in the car. He finally convined some repair shop to fix it and guess what, manifold gaskets.

Since your car has a double firewall and rubber gaskets like my 300SE, and no gasket is perfect, I still suspect the manifold gaskets. A clogged cat would also cause your problem with a swooshing sound since the cat(s) might be clogged.

Exhaust gasses are converted by the cat from mainly CO to CO2 and water. The cleaned exhaust gasses also have a sweet smell to them. If your car interior smells sweet like that, then the leak is after the cat.

Get someone to cover the pipe outlets with their hands and check for leaks in the rest of the system.

Good luck. Report back.