smoke coming from underneath.... :(
 

Filled the car with super instead of premium... it says it requires premium... but i dont know if it matters... anyway... i just got it and have never filled it with premium. after getting home from about a 150 mile trip i saw some smoke coming from underneath the car. It also kind of smelled like burnt gas/oil. the smoke was a gray color, and there was hardly any there at all, you couldnt notice unless you were looking for it. Anyway, i am wondering if this somking was possibly due to the super gas, or if the smoking was due to some kind of oil or fluid leak. There arent stains on the driveway when i move the car around, so i dont think its a leak, but im not sure. Any info would help.


Ged:confused:

What car, what year, what mileage?

Could easily be a fluid leak, maybe oil leaking from valve cover seals.

Certainly not related to gasoline grade.
Smells like oil leaking onto the exhaust somewhere.
May just not be enough to stain the driveway.

1990 300e with 178k miles... if it isnt gas... will it be bad for the engine to use super isntead of premium? ot should i stick to the hiogh octane?

Ged

I have had good results with mid-grade. Some will say this is heresy...
The compression ratio for the w124 is very high for a stock production car, so there really is some benefit to using higher octane fuel.