Review on ACDelco GM Original Equipment 213-148 Engine Crankshaft Position Sensor: Reliability & Precision for Enhanced Engine Performance by Mike Diaz

Then put on a 2000 Pontiac Grand Am GT with LA1 3400 engine I rebuilt the engine and it starts amazing but that's not because I replaced 1 small sensor: p. Anyway, it's 1 of 2 crank position sensors in case anyone is interested. This is the sensor located on the firewall side of the unit (around cylinder 3 - centre). It is directly responsible for measuring the crankshaft and starting the car. A (I think) 10mm screw holds it. And for those who replace it in the car (depending on the model), you can try to attack it from the side of the passenger wheel arch (didn't matter to me since I had the engine off, and even if it was inside it would be easy, since the engine is pretty far forward at 3400 unlike my 2005 Impala) Hope this helps and but ACDelco no problem for your GM