Mechanics

98 NOT STARTING

1998 Plymouth Neon • 4 cylinder FWD Manual • 178,000 miles

98 Plymouth neon has no spark or power to solenoid, no fuel pressure, no power going to fuel pump, blows the fuel pump fuse when turned over. Cranks over but will not start. All relays have been replaced and tested, the crankshaft sensor also has no power running to it. The ignition which is new and good. All grounds are good and tore everything in my car apart looking for shorts to no success. Possibly the ECM?
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Dave_id92
December 3, 2010.




Remove the automatic shutdown relay and see if the fuse pops. Instead of a fuse, you can rig up a pair of wires and run them to a brake light bulb, (not to the brake lights. I mean use a 12 volt bulb). Now, when the short is in the circuit, the bulb will just be full brightness, and when the short is removed, the bulb will be dim or go out.

If the fuse does not blow when the ASD relay is out, the short is on the other side of the relay. The things to look at are the ignition coil, fuel pump, oxygen sensor heaters, injectors, and alternator field. It's easy to unplug the coil pack.

By the way, the ASD relay turns on during engine rotation, (cranking or running). Rather than trying to do all the troubleshooting while cranking the engine, it would be easier to bypass the ASD relay. You don't even have to have the ignition switch turned on.

As I recall, you have the smaller relays. If you look at the pins, there are three in parallel on one end. Use the middle of those three and the pin furthest across from them. Jump those two terminals in the relay socket with a piece of wire or a stretched out paper clip. You can also hook the light bulb to those two terminals and put a new fuse in its socket. The bulb will limit current to about one amp.

If the test bulb is bright, now you can unplug things. When the short is gone, the bulb will get dim or go out. One good suspect is the oxygen sensor. The next most likely thing would be the fuel pump or wire running to it, then the ignition coil and its feed wire. Also look for a wire harness behind the engine that fell down and melted to the exhaust manifold.

Caradiodoc
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Caradiodoc
Dec 3, 2010.
I appreciate the help I'll give it all a try thanks much

Tiny
Dave_id92
Dec 3, 2010.

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