There are 3 basic things you need to start a car. If you aren't starting, then it falls into one of these 3:
Fuel
Spark
Compression
If you aren't starting, this is best way to think out what's wrong.
Fuel: Do you have fuel and are you getting it? Knowing if you have is easy, is it pumping is much harder. Clogged fuel filter, bad fuel pump, clogged carberator, etc. You may be able to pull off a fuel feed-line, have someone turn the car over and see if fuel shoots out. Don't turn the car over for long or you'll be spraying gas all over, only need a second or two. You could have an electrical gas pump (usually on/near the fuel tank) or a mechanical one hanging off the side of the engine.
Spark: pull off a spark plug wire, put an insulated handle screwdriver in the wire end, hold the body of the screwdriver 1/8" from the engine (ground) and have someone turn the car over - do you see jumping spark? If you get really close and no spark, then you have no spark. Tell the person to turn the key off. Don't electricute yourself. It is low amperage but HIGH voltage.
Compression: - much harder to check without a compression guage. But, do you have a clogged air filter? No air no air to compress. But, usually even if the air filter is really clogged an engine will still start - low mileage, low power, etc., but it will still usually start.
If you are getting fuel, spark and compression - then it starts to get interesting. Find the answer to those 3 before ever looking further.
Good luck
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What about; dead battery, bad alternator (and dead battery) or bad starter
Pulley stop truck from starting
No.
cmp snsr will not prevent the car from starting,ckp snsr would.
starter or alternator or water pump
it shouldnt.
If you have an older car that has a carburetor, the accelerator pump diaphragm may be defective
To make sure there are legal things in his car
To make sure there are legal things in his car
this question makes no sense ? i assume you mean prevent the car from cranking??? if so then no. a bad fuel pump may stop the car from running or starting but it should not stop it from cranking. a bad fuel pump relay could stop the car from cranking but that would depend on the year make and model of your car.
no.an engine can run on 3
you have a bad alternater or belt
If it's stuck in the completely open position, it can.