96 Intrepid 3.3

The most expensive and least effective way to diagnose any car is by throwing random parts at it. It will cost you less to have a mechanic diagnose the problem. In particular, other than diesel trucks, you'll never solve a stalling problem on a Chrysler product by replacing the fuel filter. The fuel pump will commonly fail while driving on GM products, but on Chryslers, they fail to start up. They rarely fail while driving. GM trucks have lots of fuel pressure regulator trouble too, but problems on Chryslers are unheard of.

The most common things that cause stalling when warm are the camshaft position sensor and the crankshaft position sensor. When they start to fail, they will work again after cooling down for about a half hour. When one of these sensors fails, the Engine Computer will not turn on the automatic shutdown relay. That removes power from the ignition coil(s), injectors, and fuel pump, through the fuel pump relay. There should be a diagnostic fault code stored in the computer indicating which sensor failed.

Before you throw in more parts, check if there's any diagnostic fault codes. Chrysler has always made that real easy to do. For a '96 model, they should read out in the odometer display. On '95 and older cars you have to count the flashes of the Check Engine light to read the two-digit codes. Cycle the ignition switch from "off" to "run" three times in less than five seconds, leave it in "run", then watch for the codes to appear. If any show up, holler back with them.

Another approach is to measure the voltage on the power feed wire to the ignition coil(s) or any injector. I think it's a dark green / orange wire. You should find 12 volts there for only one second after turning on the ignition switch. What's important is it must come back during cranking. If it does not, the cam and crank sensors are again suspect.

Rats. 12 means the battery was disconnected recently and 55 just means "end of message". If there were any other codes, disconnecting the battery would have erased them.

Grab a test light or voltmeter and check the voltage on the dark green / orange wire at the coil pack or any injector. You should find close to 12 volts there whenever the engine is rotating, (cranking or running). You can poke the probe through the back side of the rubber seal in the connector, or you can unplug the connector and put the probe right on the terminal.

You'll see voltage there for one second after turning on the ignition switch, then it will go right back to 0 volts. That voltage came from the automatic shutdown (ASD) relay which was turned on by the Engine Computer. That relay will get turned on again during engine cranking. If it does not, the computer doesn't know the engine is rotating due to missing pulses from the camshaft position sensor or the crankshaft position sensor.