The brake tapping thing was used by people to see if they had the "L" or "M" flash on the cars ECU. If you tapped the brake 20 times in 8 seconds the oil pressure guages needle will sweep to about the halfway point and go back down confirning you have one of those flashes. It has been mentioned that it does reset the ECU's memory. True or not I don't know.

btw you must have the ignition in the acc position to do this. Don't have it off or turn the car on or you won't be seeing the desired result even if you do have one of those versions.

 

This procedure (tap the brake pedal ~20 times in 8 seconds) has always been the procedure to reset the KAM (Keep alive memory) of the ECU. This particular part of the memory is not even reset when you disconnect the battery, the only way to reset it (by the layman) is to follow this procedure.

It wasn't until the "L" flash that you could VERIFY that you had completed it successfully by watching the needle sweep and return, but it's always worked.

The car runs noticeably better for the first few minutes after doing this procedure - I do it before every autocross.