thermostat stuck open, VANOS, FUEL FILTER all come to mind
check option 5 on the hidden OBDII menu and see what its telling you you should be getting, then calculate what you are actually getting. that will tell you how far off your tuning is usually
TRICK: dividing the hidden ODBII menu's nummber (ie 96 = 9.6) by 235
235(DIVIDED BY)9.6 = MPG
Driving in Clearwater FL, i just got 25mpg ON US19 (congested highway) using 93 octane ethanol free, doing conservative, but not slow driving skills. thats pretty damn good i would only get 22 on shell vpower w/ 10% ethanol before
Ran through a whole tank of it and then divided out miles and gallons.
my ODBII otion 5 said i got 27, but its always reads about 2MPG higher than what I actually get
USE Premium gas too, that will improve miles by 2MPG avg and make the car run smoother.
The ethanol free, however, made the miles go up ANOTHER 2mpg from shell v power 93 w./ 10% ethanol
Might be from one of those resister in a box performance chips. maybe PO installed it. I would try the thermostat.
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Related Threads
?
?
?
?
?
E46 Fanatics Forum
17.9M posts
592.5K members
Since 2001
A forum community dedicated to BMW E46, E90, and F30 owners and enthusiasts. Come join the discussion about M performance, turbo kits, engine swaps, builds, modifications, classifieds, troubleshooting, maintenance, and more!