Poor gas economy
 

I am getting 13 miles to the gallon. My car is not burning oil/leaking, but when I get out of my car there is a smell of fuel/raw eggs. Whats the problem? Air/fuel mixture? O2 sensor? Time for a tune up? Also my aux fans NEVER come on, the relay is fine. Its it the fans themselves? Since the fans do not come on I do not use the AC.

sorry...1992 300e 129 k mi

Edit: What model?--oops, just missed your post. The smell seems like you are running at rich stop due to some sort of computer failure to control the mixture. Many possibilities . . .The O2 sensor and cat could take on damage if left too long. Manual mixture adjustment could be a temporary fix. I will leave it to others to suggest better solutions. Cheers, Andrew Seidel.

Does it come up to temperature? I had a thermostat break such that it was always open. The engine was always cold, ran open loop, and other cold engine things. But its better than breaking such that it was always closed:eek:

The raw eggs smell is the sulphur from the catalytic converter...perhaps is clogged? That would hurt your mpgs tremendously!

I agree that if you are getting strong sulpher smells you likely have a problem with the cat converter and may need a new one. This would really screw with your mpgs.

Check coolant temp -- should be 87 C or so. If not, bad thermostat. Easy to fix.

If the temp is OK, you have a bad temperature sensor -- this is why your aux fans won't run. Get it replaced, again easy. Could have a broken wire, too, althoug this is rare with a Mercedes (NOT with Volvo, though!).

You are running in open loop startup mode -- will kill your milage, your ox sensor, and your catalyst. Catalyst is expensive!

You may also have a bad fuel distributor if you have the older fuel injection system -- common problem. I don't know when MB changed to the LH type from the K-Jetronic. If the distrubutor is bad, it will be expensive to fix, and my mechanic has been having fits getting good replacements -- put three on a car before he got one that lasted more than 5000 miles! If it is bad, you will be trailing black smoke!

Peter

The smell is a catylitic issue..what ever else is in play the smell is the catylitic converter

brian