I came across this statement while I was surfing today and I wanted to see if an experienced member could verify whether or not this statement is true.

"You can try pulling the fuse to the ECM with the ignition key in the on position and then putting back in after a few seconds. Then start the car, it may stall but let it and just start it over again. The ECM is just learning the engine and transmission again, making adjustments like it's the first start up during manufacturing and go for a test drive."

I believe the statement is referring to diagnosing a bad MAF sensor.

I'm just curious.

 

The ECM usually has 2 fuses. Its always been my method to remove both fuses for a min or so with key off (same result as disconnecting battery) and then re-installing them. and starting the vehicle.

If you're trying to diagnose a bad MAF, with the key off just unplug it and then start vehicle. If it runs like it's sposed to then ya know where the problem is.

-just my .02

 

Removing the fuses and or disconnecting the battery will turn the check engine light off if there are no hard faults present. It will not clear any DTC's that might be in memory or fuel trims, or reset IM readiness monitors. If the check engine light was on before pulling the fuses, and off after replacing the fuses, as soon as the affected monitor runs and completes its test, and the test fails, the light will come back on. There are no "adjustments" or "learning" that goes on by pulling fuses or disconnecting the battery.

Use a scan tool and the diagnostic flow chart to diagnose a faulty MAP sensor.

 

Actually.... there is a "relearn" going on. the computer is programmable read only memory. if you clear the memory the computer is working with the onboard systems and learning the vehicle again. it doesnt mean it wont throw you codes again in 40 miles.
(quoting the manual here)
"disconnecting the power to the ECM/PCM to the clear the memory can be an important diagnostic tool, especially on intermittent problems".