If the crank sensor came from the dealer, it had a paper spacer glued to the end. It slides off as soon as you crank the engine, but by that time its job is done. If you install a used sensor, the dealer's parts department has replacement spacers. Most aftermarket sensors have a thin plastic rib molded on the end to set the air gap. If you reinstall one of those, you're supposed to cut the remaining part of the rib off, then use a paper spacer.
If there was no spacer on a used sensor, it is possible to stick it in too far and the ring on the flex plate can break it. Some people think they can just stick it in as far as it will go, then pull it back 1/16", but that usually doesn't work. Pushing it in all the way could place it exactly where it is supposed to be, then when you pull it back, the gap is too big. That results in a no-start condition or intermittent stalling.
Saturday, July 29th, 2017 AT 7:49 PM