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Crankshaft position sensor 1999 oldsmobile alero 2.4

My car start made a noise and shut down. Every time I try to turn it never cranks up. It feel like it want to start but never does. My fuel pump is working cause i can smell gas in the engine so it show i drowning the engine. I check the spark plug and they are as well as the coils are good. Im thinking its the crankshaft position sensor but i dont before i buy the part. I need your help to make sure thats what it is. please help.

You said the plugs and coils are good, but did you actually check for spark and verify that the plugs are not sparking?

As mentioned above, ask your mechanic to check for spark at the spark plug. If none is observed – and that seems possible with the symptoms you describe – it could be caused by more than one problem. Crank sensor, cam sensor, ignition module, ECM, coil(s), plug wires, distributor (if your car uses one), timing belt, etc … If you want to use the ‘ol replace it and hope that’s the problem’ technique, then yes the crank sensor would be a reasonable place to start.

The problem is that while that technique worked pretty good on 1980’s & earlier pre-electronic-fuel injection cars, it isn’t nearly as effective on newer models, like yours. It’s easy to run out of money replacing stuff that was never broke in the first place, before ever finding the problem. Then you end up with a car full of aftermarket parts that are less reliable than what was originally in there, and you still have the same problem. It’s usually more cost effective to get a proper diagnosis first.

If I had this problem the first place I’d check is for any diagnostic trouble codes from the ECM memory. You paid for this ECM diagnostic function the manufacture provided, so you might as well use it. If you can get those codes read and post them, folks here who have experience in those particular codes can give you more specific advice on what to do next.