Fumes when driving

[Tof]

Hi,
I have a 420 SEC Mercedes. If window is open when driving i get a strong smell of fumes in the car. No smell if idle or stopped. Only when it gets to 5/10 m/hr. Any advise would be appreciated.
Cheers
Tony

 

[alexanderfoti]

Is the exhaust in good condition? No leaks around the center section of exhaust manifold side?

Do check for rust in the rear quarters behind the arches. A low pressure zone will cause exhaust gasses to enter the car through these.

Also check the boot seal for the same reason.

 

[Tof]

Thanks for the reply. No leaks on the exhaust. Had it checked with a specialist. Just wondering if that it only happens with windows open would be obvious to anyone?

 

[M80]

A blocked pollen filter?

 

[alexanderfoti]

Thanks for the reply. No leaks on the exhaust. Had it checked with a specialist. Just wondering if that it only happens with windows open would be obvious to anyone?

Yes, this causes a negative pressure inside the car which causes air to get sucked in through any available space. Rust holes and failed seals are a favorite.