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Injectors not priming

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Old 02-14-2018, 04:59 PM
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Injectors not priming

Ive got a 1988 chevy 3500 with a 350 tbi. When i turn the key on the injectors will not prime so the truck will not start. If i manually prime the throttle body it will fire up and run i just cant ahut the truck off unless i pop the hood and prime it manually again. I have no idea what i need to try. Any suggestions?
Old 02-14-2018, 05:32 PM
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Car: 1967 Camaro, 91 z28
Engine: Lb9
Transmission: M20
Axle/Gears: J65 pbr on stock posi 10bolt
Re: Injectors not priming

Check the power to the fuel pump relay.

Old 02-14-2018, 05:57 PM
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Re: Injectors not priming

Ground signal is hooked up. Has no slices or amytging in it. I just got it to fire up 1 time on its own but wont do it again
Old 02-14-2018, 06:06 PM
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Car: 1967 Camaro, 91 z28
Engine: Lb9
Transmission: M20
Axle/Gears: J65 pbr on stock posi 10bolt
Re: Injectors not priming

Iirc there is a wire that goes to the starter. This wire gets power during cranking and the ecm adds fuel when it gets powered up. I think it helps for cold starting pin c9 at the ecm.
Old 02-14-2018, 06:12 PM
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Car: 1967 Camaro, 91 z28
Engine: Lb9
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Axle/Gears: J65 pbr on stock posi 10bolt
Re: Injectors not priming

Have you checked fuel pressure ?
Old 02-14-2018, 06:20 PM
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Re: Injectors not priming

Fuel pressure is good
Old 02-15-2018, 07:37 AM
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Re: Injectors not priming

Do you have "good" fuel pressure when turning the key from "Off" to "Ign"? You should have a 2-second pulse of fuel pressure which will immediately drain off and go back to zero.

No 2-second pulse of fuel, ECM is faulty, Fuel pump relay is faulty, or the wiring harness (including fuses) is faulty. You HAVE checked the fuses...right?

The engine should still start if you crank it long enough to build oil pressure--the oil pressure switch should bypass the ECM and fuel pump relay to power the fuel pump. If not, then you've got additional problems with the pressure switch or wiring harness.
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