View Single Post
Old 12-17-2013, 12:02 AM   #135
tw
Read? I only know how to write.
 
Join Date: Jan 2001
Posts: 11,933
Quote:
Originally Posted by xoxoxoBruce View Post
They don't get better mileage, they have more detergent(s) to keep crap from building in the motor,
Mobil (decades before it became Exxon) had a highest detergent gas. It was not on the approved BMW list. Another study noted excessive detergents in Mobil resulted in carbon build up on valve stems.

Nothing previously discussed detergents. Additives mean more gas burns productively in the engine.

One night twenty some years ago, a Mobil station was the only open station. Next day, I knew something was wrong. Numbers confirmed it. Next tanks were a pathetic 27 and 25 MPG. I knew exactly when it happened - right after filling up at that Mobil station. The dealer identified damaged fuel injectors. I paid nothing to replace $400 of injectors. Mileage restored to above 30 MPG.
tw is offline   Reply With Quote