Engine runs for two seconds and shuts off

1995 OLDSMOBILE 88
55,000 MILES • 3.8L • 6 CYL • 2WD • AUTOMATIC
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SEANH51
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3800 mk2 stalled and shut off at idle. Since then have changed crank and cam sensors, all intake gaskets, and temperature sensors. Plugs are soaked in fuel, plugged in scan tool. Injector pulse is at 66ms for cold start. All other data (ambient temperature, water temperature, O2 sensors, TPS) is exact in range. What's happening here?
Jul 8, 2020 at 12:36 PM
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ASEMASTER6371
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Good afternoon,

I would check the fuel pressure regulator. there is a vacuum line on the regulator. Remove it and turn the key on. See if any fuel comes out of the port on the regulator.

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

I attached a picture of the location for you.

Roy
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Jul 8, 2020 at 2:16 PM
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SEANH51
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Fuel pressure holds steady at 53 psi. No leaks in the regulator.
Jul 8, 2020 at 2:25 PM
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ASEMASTER6371
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Okay, good. Then you must be losing spark.

Does it start right back up after it shuts off?

This could be a module, coils or a crank sensor.

https://www.2carpros.com/articles/how-a-crank-shaft-angle-sensor-works

https://www.2carpros.com/articles/crankshaft-angle-sensor-replacement

https://www.2carpros.com/articles/symptoms-of-a-bad-crankshaft-sensor

I attached wiring diagrams for you to view. Do you have a test light and a voltmeter to do some testing?

https://www.2carpros.com/articles/how-to-check-wiring

Roy
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Jul 8, 2020 at 2:33 PM
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SEANH51
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I have good spark. I have good fuel pressure and flow. I have compression. The PCM is hanging injectors wide open and flooding cylinders. Only starts and runs for 1 second. Will not restart unless I dry plugs because they are soaking with fuel.
Jul 8, 2020 at 2:49 PM
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ASEMASTER6371
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Okay, then you have a bad ECM. The quad drivers are not working correctly.

Roy
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Jul 8, 2020 at 2:55 PM
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SEANH51
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Thank you.
Jul 8, 2020 at 2:58 PM
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ASEMASTER6371
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You are welcome.

Always glad to help.

Roy
Jul 8, 2020 at 3:14 PM