Engine shuts off after 25 minutes?

1995 MERCURY MYSTIQUE
131,000 MILES • 2.5L • V6 • 2WD • AUTOMATIC
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QFONG
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After the engine idles for about 25 minutes, it shuts off and will not restart. The PCM/ECM is very hot to the touch. I can smell unburned gas when I try to restart.
Apr 3, 2023 at 11:58 AM
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STRAILER
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The PCM should not be hot, it sounds like you have a shorts injector, ignition coil or a bad ground to the PCM, can you see if the coil is hot as well, if so, I would replace it with a new one. Check out the images (below). Please let us know what happens.
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Apr 3, 2023 at 3:41 PM
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QFONG
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The PCM should be grounded from terminals 20 and 60, is that correct? The coil pack is new. It was warm but it sits right over the bank 1 exhaust manifold. I will investigate tomorrow.
Apr 3, 2023 at 5:36 PM
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STRAILER
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Here are the PCM wiring diagrams so you can see which wires are power and which are grounds.

This guide can help you check:

https://www.2carpros.com/articles/how-to-use-a-test-light-circuit-tester

Check out the images (below). Please let us know what happens.


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Apr 4, 2023 at 10:06 AM