How to Replace the Crankshaft Sensor on a Nissan Altimaby Don Bowman
The crankshaft sensor on 1999 and earlier model Nissans is located in the bellhousing, on the radiator side. It faces in toward the ring gear on the flexplate. The 2000 and later Nissans have the crankshaft sensor and cam shaft sensor located within the distributor and are non-serviceable. The distributor must be replaced in the event of a failure.
Remove the electrical connector from the crankshaft sensor. Push in on the green tap until it clicks, freeing the lock on the sensor connector and allowing extraction.
Remove the 10mm bolt in the crankshaft sensor bracket. The best thing to do here is to loosen the bolt, then remove the bolt by hand so it does not drop and get lost.
Grab the sensor and twist it to the left and right to free the O-ring inside the bellhousing. The sensor is a tight fit with the O-ring in the housing. Use a common screwdriver to pry gently under the bracket extension where the bolt was removed.
Insert the new crankshaft sensor using a drop of oil on the O-ring to ease installation. The sensor will go in up to the O-ring and from there on it will require a small amount of force to pop it in. To be on the safe side, push it in with a common screwdriver, putting the tip of the screwdriver on the bracket extension. Push it in far enough to get the hold-down bolt into the bracket with a couple of threads. Tighten the bolt and draw the sensor in.
Plug in the crankshaft sensor electrical connector and make sure that it locks in place with a click. Give it a little pull to see if it is indeed tight and will not come off. If it does come off, the vehicle will shut off immediately.