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Nick_R_23 · 11-28-2021, 07:32 PM

You may have a failing diode pack on your alternator. While the truck is running, take a multimeter and set it to read AC (~) current. Put the red lead on the alternators 12V stud, and touch the black lead to the alternator body. You should not get any voltage readings, if you do, your alternator is introducing AC voltage into the system, which can definitely mess with the ECU and sensors.

11-28-2021, 07:32 PM	#17
Nick_R_23 Registered User Join Date: May 2016 Location: Willow, Alaska Posts: 839	Re: Quick distributor question... You may have a failing diode pack on your alternator. While the truck is running, take a multimeter and set it to read AC (~) current. Put the red lead on the alternators 12V stud, and touch the black lead to the alternator body. You should not get any voltage readings, if you do, your alternator is introducing AC voltage into the system, which can definitely mess with the ECU and sensors.