Pretty sure according to the long term fuel trim, I'm running lean. The only reason I even noticed, my mpg dropped down to 12, from 14.5. After changing the battery and spark plugs. There's no check engine light, and it doesn't run noticeably different. I'm gonna check for vacuum leaks, but if that fails, where should I look next?
4runner running lean
- Thread starter Sr Auron
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Stick Figure
New member
My first question would be how long has it been since you put the new battery in? Unless you use a back up battery to keep power to the ECU, you just lost all of the info it had stored.
octanejunkie
Elite Member
Those screens look like startup values. What are your fuel trims after reaching operating temp and driving for at least 20 mins?
thecole1098
New member
Looks like closed loop to me. The thermostat opens around 175 and his idle was 725, which is "in spec" for operating temp. But agreed about driving around for a bit. Ideally you want your LTFT to be right at 0 give or take 5%.
No, no check engine light either. I just magically lost at least 2mpg.
:welcome:
It should be at operation temperature since it reads 177 degrees.
It should be at operation temperature since it reads 177 degrees.
octanejunkie
Elite Member
That's not a vacuum leak, that's a screen door on a submarine :guitar3: