what went wrong

[matarm]

I have a 95 f250 with a 7.3 l powerstroke. I bought the truck in august and no problems. It got colder and I started having trouble with cold starts. I tested my glow plug relay and found that it was not working. I decided then to make a push button activation for the glow plugs. I cut an extension cord and placed wire connectors on the ends. I placed the wire connectors on the two small posts on the relay. My thinking was that if that was an open circuit I could use the button inside the truck to close the circuit and activate the glow plugs. The first time I used it worked perfectly. I saw the amps draw down and the truck fired right up. The next time I tried the amps didn’t draw down as much. Then the third time it didn’t work at all. I then removed the glow plugs and found that all 8 were not burned up. They were autolite plugs,and from what I hear I am lucky they didn’t swell and break off. I assume that I did something wrong in this process causing the plugs to fail. Any ideas on what I did.

[jesilvas]

They could just gone bad. As long as you only used your DIY setup to power the low amp circuit that engages the relay then you shouldn't have messed anything up. The relay couldn've just gone completely out. Just get a Stancor relay to replace the OEM GPR and get Motorcraft (Beru) GPs. You should also check the UVCH to make sure it isn't the problem.

[weareweird69]

He basically nailed it.

Replace the glow plugs with Motorcraft ZD-11's and get a Stancor Relay, call Complete Performance Complete Performance

Youll never have problems starting in the cold again.

[ianstew]

+1 on the stancor, i have had no problems what so ever. i moved mine off the engine though, i read quite a few things about heat and vibration not being ideal conditions for a relay.

[lwillson]

One of the small posts on the GPR goes to the battery, and the other one goes to the PCM. The PCM grounds the terminal, closing the GPR.

For your button to work, you would need to wire one end of the button to the PCM lead of the relay, and the other end of the button to ground