In the past 2 weeks I have replaced the Fuel Pump Relay and Ignition (Power) Module. My car still stops running without warning. In all cases, the car starts up immediately. Does anyone have any suggestions on what the problem might be. Thanks for your input.

You can be sure that it does stop for a reason.

Watch the tach carefully when it happens. If it drops to 0 even before the engine winds down then that would indicate loss of ignition pulses to the coil negative terminal. Primary suspects would be the power stage or the crank position sensor.

If tach tracks the engine speed as it winds down then that would indicate a fuel problem. Suspect radio supression relay, or loss of fuel pressure due to relay or pump.
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David Hunter

I would suspect the crank sensor (aka engine speed sensor or RPM sensor) that's behind the head, on top of the trans bell housing.
Also, there is another relay, the Ignition Suppression Relay that you will want to re-solder or replace. The FAQ diagram should point that one out to you.

Good luck, hope you find it before it leaves you stuck!
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Rob Bareiss, New London CT ::: 'Roterande Fläkt Och Drivremmar!'

I second, or maybe third the hall/speed/crank sensor. This sounds suspiciously familiar. My Wagon would quit announced. Then start 5sec or up to 30 mins later. 15-25$ part - go for it!

Tim
1990 745T
1993 944T