Exhaust Fumes

[sammyr]

My 69 sl has alot of exhaust fumes. It smells like gas...maybe raw gas?? Any one ever had this probelm? Any suggestions?

[Cees Klumper]

Hello Sammy - check the cold start injector on the intake manifold. If you do a search on this widget on the site you will find the testing procedure, it involves taking out the little bolt on the side to see whether it leaks. This could cause fuel smell from the exhaust (never noticed this on my car) as well as account for poor mileage AND rapid engine wear due to the gas washing the oil film off the cylinder walls. Other than that, I suppose the FI pump / mixture could be way off, or incomplete combustion due to other tuning problems.

Cees Klumper in Amsterdam
'69 white 280 SL automatic

[Jonny B]

Don't forget to check the gas tank vent hoses and tubing in the trunk, there is a lot of information on the site about how repair these. Another indicator is a whooosh sound when you open the gas tank to fuel up.

Jonny B
1967 250SL Auto

[Shvegel]

I had this problem after I rebuilt my engine. In my case I had miss-timed my engine and had set the timing too far retarded so the fuel was not completly burned in the engine.