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Discussion Starter #1
okay guys so here is the deal, a few weeks ago I picked up a 95 f350 with the 7.3 diesel. I am new to owning a diesel and kinda lost. It fires up very well but from what I can tell it is not firing on the front 2 cylinders on the passenger side. I have tested all the wires in the valve cover harness and they have power and when I check for resistance I cant seem to find any indicating that the wires are good.. I think. i have replaced those injectors and no change. it doesn't make very good power and i am at a loss. i have been under the hood all day and tested everything i can think of but cant find the problem. i am trying to avoid going to the dealership as they want about 120 dollars an hour and i cant afford to do that. any suggestions would be greatly appreciated and checked out to the best of my abilities. i apologize in advance for any dumbing down that your suggestions may require
 

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Welcome!

Here are some tests you can do (and you may have already done some of them). Make sure that your DVOM is set to the correct scale for each tests (based on the resistance you should see).

For checking the injector/glowplug wiring: From each valvecover gasket connection's outermost pins (2 per connector) to ground you should get 0.1 to 2 ohms (indicates good plug and wiring). From each valvecover gasket connection's center pin to each immediately adjacent pin, you should get around 3 ohms (indicates good injector solenoid and wiring). You should not get any continuity from any of the outer pins to the 3 inner pins (indicates no shorts between injector and glowplug wiring). You should also get 0 to 1 ohms from each of the external harness connectors outer pins back to the Glowplug Relay's large terminal on the GP side (indicates good wiring from external connections back to the relay).

To check the glowplug relay (GPR), measure the voltage drop across the GPR's large terminals. While the GPR is active (up to 1.5 to 2 minutes after the key is turned to Wait-to-Start) put your meter leads on the large terminals (one lead on one large terminal and the other lead on the other large terminal). The measures how much voltage is being "lost" across the relay. A reading of 0.3V or more indicates a bad relay. Also, check the relay’s control wires (smaller wires) disconnected from the relay for battery voltage at the Red/Light Green striped wire and ground at the Purple/Orange striped wire (check both when the key is turned to Wait-to-Start).

Cheers!
 

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Discussion Starter #4
well no solution yet... was worried it might be head gaskets so rented a block tester and got nothing. truck now has an overheating problem. heater never even gets warm, like to coolant goes from cool to boiling. has new thermostat and replaced the water pump yesterday... getting expensive.
 

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did you check the thermostat in a pan of boiling water before you put it in? I have had a bunch over the years that have been bad out of the box. So I always check them before installing
 

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Have you only tested your UVCH,s While they are installed. I got some bad ones a couple years ago that went out 10 miles after I installed them. But test after test after test I was getting good continuity and good resistance. After finally pulling the valve covers and inspecting them visually I discovered it, even though they were brand new, the wires and already cracked and wor while they are installed. I got some bad ones a couple years ago that went out 10 miles after I installed them. But test after test after test I was getting good continuity and good resistance. After finally pulling the valve covers and inspecting them visually I discovered it, even though they were brand new, the wires are already cracked and we’re arcing thus causing a short. A new set of wires and the quarter trick Fixed me right up
 
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