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Hi, I have a 1993 Chevy 6.5l turbo diesel that I just put a engine. I know the engine is good but I don't know about the injection pump, but I am at a complete loss I don't know if the injection pump is shot or what I know that the lift pump is good but I don't know.

any information will help I just don't know.
 

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Welcome to DieselPlace
Please give us a little more info on why you think the injection pump is shot.
Please list Make, Model and any mods.
(y)
 

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Did you change the fuel filter? I would verify you are getting fuel past the fuel filter with the key in the ON position. You should hear the lift pump running and have fuel past the filter.
 

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I believe that's in error. If it's a '93, the lift pump gets power from the start contacts of the ign. switch. Once the eng. has oil pressure, the oil pressure switch has a set of contacts that power the lift pump using a relay on the firewall. I've tried to attach a wiring diagram that explains the circuit.
 

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On a 93-95, the OPS controls the Lift Pump when engine is running.
The part of OPS that control the LP is different than the one goes to the gauge.
So the gauge can still show pressure but the LP is not running as soon as the engine catch, hence, causes stalling and inability to start.
 

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TO the OP. Maybe you should tell us what the problem is. Cant get the engine started? Not running right? More detailed info will help.
 

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Jumper the relay on the firewall to manually run the supply pump.

Check the ESO wire at the IP for power with key on.

Loosen the high pressure lines on the driver side injectors and crank the engine 10s at a time with 2 minute rests until you get fuel at the injectors.

Retighten the lines and then see what you've got.
 

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I believe that's in error. If it's a '93, the lift pump gets power from the start contacts of the ign. switch. Once the eng. has oil pressure, the oil pressure switch has a set of contacts that power the lift pump using a relay on the firewall. I've tried to attach a wiring diagram that explains the circuit.
Thanks for the correction. I remember with my truck being able to hear the lift pump clicking when the key was in the on position, although now that I think about it I am pretty sure my father in law re-wired it for troubleshooting before I bought the truck so you could hear the lift pump running. Not exactly as safe bypassing the oil pressure switch.
 
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