It is possible the teeth on the starter are damaged, or the starter's solenoid is not engaging the teeth to the flywheel.
This is easily checked by watching the engine while someone turns the key. If the belts turn, the starter is okay.
If the starter is not the problem, begin by having the computer scanned for any codes.
If there are no codes, then you will have to narrow it down the old fashioned way.
No starts are diagnosed as follows.
Ignition: (Spark at plug, wires, coils, related sensors)
Fuel: (Pressure from pump, injectors firing, related sensors)
Compression: (valve timing, broken timing chain/belt, etc.)
Sunday, November 14th, 2010 AT 6:44 PM