Weak pulse to injectors

1989 FORD E-SERIES VAN
265,000 MILES • 5.8L • AUTOMATIC
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JOE21972
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Van will start if slight push on accelerator petal. With noid tester installed after a few seconds it lights very dimly. When pushing accelerator petal it brightens and van starts. Runs very poorly. If I keep feathering pedal every push noid brightens then dims again. Will not idle. Slows down and dies.

Fuel pressure is constant around 41 lbs. all injectors pass ohm test. Around 14.7 ohms. Wiring good from plug at front of engine.
Engine was recently rebuilt. Ran for a few days then problems. The icm failed. Ended up installing a new distributor and icm. Tried two eec. Same deal on both. Checked grounds all seem good. I don’t have a wire diagram or know what the PIN numbers are in the eec to test there.

If I spray fuel into the intake it runs good.
Also when running on the injectors it will not rev past about 1200 when feathering throttle. Dies if I just push throttle down and hold. Any ideas or directions?

Don’t know what I’m missing. Can get video of what it’s doing tomorrow
Aug 4, 2026 at 8:46 PM
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STRAILER
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Yes, please upload a video that will help. The light injector is a concern for sure, when cranking the pulse would be bright until the engine starts then it will calm down when at idle. Here are the wiring diagrams for the ICM and fuel injectors so you can test and see how the system works, but I need to say the fuel injectors can test well but then under load fail, please watch this video to tell you why.

https://youtu.be/2dYGZNaHpUA?si=lcaCBpGBRl3OGC0k

Also, I would try unplugging the MAP sensor to see if that helps, please let me know.
Aug 5, 2026 at 12:21 PM
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JOE21972
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Sent two videos. First is no throttle. Second is when I step on throttle. Noid brightens momentarily then goes back to dim and won’t run
Aug 5, 2026 at 12:24 PM
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JOE21972
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Ok I’ll try tonight when I get back home
Aug 5, 2026 at 12:25 PM
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STRAILER
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Okay, the pulse looks okay on the injectors, I don't think hat is an issue, is there a chance the catalytic converter is clogged? Does this van have one?
Aug 5, 2026 at 12:27 PM
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JOE21972
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Cat is not there
Aug 5, 2026 at 12:54 PM
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