A diagnostic test might be a lot cheaper than throwing a bunch of parts at it. First you need to determine if spark, fuel, or both are missing. A fast way to determine if both are missing is to use a test light or voltmeter to monitor the voltage on one of the small wires plugged into the back of the alternator. Near battery voltage should appear for two seconds after turning the ignition switch on, then it will go off. If it appears again while cranking, the Automatic Shutdown relay is turning on. That tells you the crankshaft and camshaft position sensors are working properly.
It's not likely a fuel pump would quit after it's up and running. It IS common for the ignition coil, cam and crank sensors, and other electronic parts to fail when they get warm. A MAP sensor can do this, but it will usually set a diagnostic fault code and turn on the "Check Engine" light. If the MAP sensor is bad, very often the engine will start and run as long as the gas pedal is moving.
When the engine stalls, try to observe if it's sudden, such as when turning off the ignition switch, or if it sputters and slowly dies out. Dying suddenly is usually electrical; slowly dying is most likely a fuel problem.
Be careful when replacing computers. If you put in a body computer or an engine computer from a car that has the anti-theft system and your car does not, one will self-program the other into thinking it's on the car, and it won't start. The same thing can happen if your car has the anti-theft system but you borrow a computer from a car that doesn't have it. When you put the borrowed computer back, it will self-program the body computer, and both will have to be replaced. Once either of these computers become programmed to look for the disarm signal at startup, the programming can not be undone.
Friday, April 3rd, 2009 AT 12:21 AM