Thread: Fuel economy
View Single Post
Old 12-30-2012, 08:50 AM   #20
Registered User
Join Date: Nov 2009
Location: Fairfax, VA USA
Posts: 16,573
My Ride: 330CiC, M5, X5
The real question is what is the coolant temperature?

These thermostats fail open ALL the time and the engine can run too cold, when this happens, fuel economy is the first thing to take a dive.

95C is about typical, maybe slightly higher.

Hidden OBC will answer this question in a single trip.
Solve your misfires, lean codes, rough idle -

Fuel pump failures -

Temp Info -

Hidden OBC Menu - Check Voltage, Temp, Fuel Level -

E46/E39 GM5 Door Lock Info -

Lower hose temp switch O-ring - BMW #13621743299
jfoj is offline   Reply With Quote