GP controller troubleshooting.....

[Jamie]

Is there a sure way of testing the controller? I have tested the glow plugs using the test light method and they all check out. I replaced the solenoid on top of the timer, I am still getting a steady "clicking" from the black box. Does this confirm that it has failed? The wait to start light is staying on for approx. fifteen seconds, but only for two seconds when I attempt to cycle them.

The truck will not start. It sounds like it half fires once in a while.

Thanks in advance,

 

[79GLIDE]

I had a similar situation with my relay/solenoid, repeated clicking sound and no start after cycling the glow plugs. The advice that worked for me was to hold the accelerator to the floor while cranking. You can set the fast idle for start up by turning the key on, then pushing the accelerator to the floor and releasing, the accelerator returns only part way to idle position, then crank to start. My truck, 1994 F350 turbo, would never start doing this if it is less than 35-40 degrees outside. However, if I hold the accelerator to the floor while cranking, it will start most of the time above 20 degrees. Once she fires and surges a bit, I let up on the accelerator and the truck idles. I have posted previously that the relay continues to click repeatedly after starting and apparently this is a normal expected cycling of the glow plugs under cold start situations. I'm interested to see what your results are with this advice. Hope it helps.

 

[Ironman03R]

What you describe sounds normal, WTS light shound stay on about that long the first time, but anything after that will be quicker due to the system already being hot.
I'd check for air leaks on the return caps, check both batteries and all connections. If theres air in the system or the engine wont spin fast enough it wont fire.
Also as previously stated, you need to push down on the accelerator to get the fast Idle sol to engage

 

[Jamie]

Thanks for the input guys. I have kinda done things a _ _ backward apparently. I did find two bad glow plugs and changing them did not seem to solve the problem, I went ahead and installed a new controller at lunch time. I did not try starting it yet as it is - 35 celsius outside and it has not been plugged in for a few days.

Come five o'clock it is time to give her a spin though. I will let you know how things go.

 

[HammerDown]

...my GP-controller hasn't "click repeatedly " in years...still starts in sub freezing temps no problem.

 

[Jamie]

Bad news..... The truck is even less close to starting now. Here is what has been done: Replace GP controller
Replace two bad plugs
Fuel system prime

Can anybody advise what I should do next? Actually I am going to abandon ship until this weather breaks anyhow so I will have some time to regroup.

Thanks again guys.

 

[79GLIDE]

Extension cord and encouragement in a can, if your brave like me. Although not a recommended practice, I have been saved by ether more than once in the past few weeks.

 

[Jamie]

That sums up about where I am at. I am pretty confident there is no glow plug action at this point, at least then I could drive it somewhere so I can wok inside.

 

[Ironman03R]

DO NOT use either with the GP system hooked up! Even if your sure they dont work unhook the controler just to be safe. Be sure the batteries have a good charge, if they are gettig weak you could fry the starter.
You can manually test the GP system by grounding the white wire on the controler for a few seconds. This will turn the plugs on. Dont ground it for more than about 5-7 seconds each time.

 

[Jamie]

I will try this method of manually running the glow plug system this evening. Can a person tell the glow plugs are energized while attempting this?

 

[Jamie]

One more thing, what is the best way to disconnect the GP system in the event I am going to attempt an ether start? Can I simply disconnect the wire going to the computer?

 

[Ironman03R]

When the relay clicks, they're on. Just dont let them on too long or they will burn out.
To disable it I would disconnect the keyed ign on, that will not activate the controler.

 

[Jamie]

This just keeps getting better.... The truck still will not fire, even with an ether shot. Is this even possible? Hopefully this may offer further clues to what is going on here. Let me recap how this whole thing started.

The system the previous owner had retrofitted on the truck to enable manual high idle control failed. turns out the system was some how interfaced with the cold start switch. I try to start this thing in cold temps without the aid of the cold start solenoid, to no avail. I run down the batteries in doing so.

I take the batteries to work, load test and charge them. Upon reinstallation into the truck, the manual high idle control seems to be functional again, I assume the cold start function is once again available.

Batteries fully charged, warm engine from block heater, the thing will not start. A friend suggest I go ahead and swap out the GP controller.... I do so. I find two bad plugs, I change them. I prime the fuel system.

This brings us to today. I am becoming quite frustrated as I know this must be something so simple causing this. The truck started and ran very strong up until the malfunction with the idle control.

Sorry for the long windedness, thanks for listening in any case.

Jamie

 

[smokin69]

Are you sure the wire to the FSS is conected and that it's not all corroded?

 

[Jamie]

Can you elaborate for me, I am unsure what the FSS refers to. Is there a diagram or a photo around of what the IP wring should look like?