E46Fanatics - View Single Post - CEL light on....SAP bad and other engine performance problems
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Old 01-18-2013, 03:26 PM   #9
OEM ///Member
Join Date: Nov 2009
Location: Fairfax, VA USA
Posts: 23,201
My Ride: 330CiC, M5, X5, E93

Also forgot to mention you need to provide both idle and cruising Fuel Trims at some point.

If your car is running rich, the fuel trims will be negative or proceeded with a - sign, they will be displayed like -2.3%.

If your car it running lean, which happens most often your fuel trims will be usually not be proceeded with a value or + sign, they will be displayed like 3.4%.

In my world I try to keep my fuel trims under 3%, prefer under 2% but sometimes this is not very feasible.

Forget about anyone that tells you that fuel trims just below 6% are fine, they may not trigger a CEL but they are NOT fine. This is too close to the threshold for triggering the CEL.
Solve your misfires, lean codes, rough idle - http://forum.e46fanatics.com/showthread.php?t=897616

Fuel pump failures - http://forum.e46fanatics.com/showthread.php?t=929501

Temp Info - http://forum.e46fanatics.com/showthread.php?t=964491

Hidden OBC Menu - Check Voltage, Temp, Fuel Level - http://forum.e46fanatics.com/showthread.php?t=239619

E46/E39 GM5 Door Lock Info - www.bmwgm5.com

Lower hose temp switch O-ring - BMW #13621743299
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