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Glow plugs not working/ lift pump constantly running?

H

hardwick

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I recently installed a new 6.5 TD in our '94 3500 dually. Two main problems occured after installation.
First, when the key is turned on the lift pump constantly runs before it is even started. Already replaced the OPS that regulates it and still same result.
Second, there is no power to the glow plugs whatsoever. All the lights are also working, but the gauges all read weird. With brand new interstate batteries, the gauge only reads 10 amps and the fuel gauge is pointe at about 5 o'clock. Dont know what was missed but im stuck here. Maybe mixed wires somewhere?


****Forgot to mention, truck has yet to be started tho it has been turned over only but only to raise oil pressure high enough but has not been started as of yet.
 
What year of truck? OBD2 lift pump will run with key on. You may have missed some grounds, that could explain the gauges.
 
The OPS only controls the Lift Pump when there is oil pressure. Your lift pump relay on the passenger side firewall may be stuck closed. Never seen it but its possbile. Unplug the relay and see if it shuts off with IGN power. It could be that someone added ignition power to the wire that goes to the Normally Closed contact of the LP, which ends up at pin G of the OBD DLC connector. With the IGN on there should not be 12V at pin G, and if there is then power is getting through the OPS or someone added a line.

For the Glow Plugs, did you check the Glow Plug Fuse under the steering column?

Is the truck starting? Is there an SES light when you turn the key to ON? If not then your PCM is not getting power or is not grounded. First check ECM fuse under steering column, then go check the grounds on the back of passenger side intake. There should be one on an intake bolt and another right behind the intake there on the coolant block off plate stud, that has wires coming into one terminal. Then there should be another on the back of the head somewhere against the firewall closer to the fuel filter.
 
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