Hopefully this will save someone some time and trips under your car.
I changed the crank position sensor in my NB Miata. I gapped it toward the close end of the range which is according to the internet 0.020-0.059".
I started at 0.022" then took it for a short drive. It was misfiring over bumps so I brought it home and re-gapped it. Went for a drive still misfiring. I gradually widened the gap in increments of 0.002" until I got to a gap of 0.044".
It took a number of trips under the car to get it to that point, no matter what I set it at it would misfire over bumps some settings worse than others.
Frustrated, I set the gap to .024" and called it a day.
The next day, I took it to work. As expected, it was misfiring over bumps sometimes pretty bad. At lunch it was misfiring but not as bad. On the way home it misfired over a particularly bad bump.
I went for a drive after I got home. No misfire. It has been fine ever since
What I think I learned is; if the gap is set within the proper range, the car will run but is more prone to misfire until the new gap is learned by the ECU. If that is the case, the many trips I took under the car were unnecessary.
If my logic isn't correct can anyone explain why the misfire stopped?
