Previous difficult cold start > Now it seems like not getting fuel and won't start at all

Baxter

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About my 1993 7.3 idi w/turbo ...Well, I thought I could use the block heater to bypass glow plug system. I'll try to be a brief as possible here to explain ... first time using it ..Plugged in block heater for about 2-3 hrs. on a relatively warm 60 degrees F evening... I could hear the buzzing noise and it heated up the engine bay pretty good, engine block was warm to the touch... Wasn't enough to start the truck. >> Fast forward to I installed the CDD manual glow plug switch wiring kit. Thing is awesome and well put together. (Should mention I basically just cut all wires going to the stock gp controller/relay unit.) Tested glow plugs beforehand and they appeared good showing about .4 - .5 on the meter. Got in truck held the button for about 8-10 sec. ... nothing .... just cranking and cranking. paused for starter ... throttle pedal to the floor ... cranking cranking... nothing. Same as before. Several months ago when I had the hard cold start issue I was able to get it fired up after many trys and plenty of throttle. Truck would then run perfectly smooth and strong. Did this maybe on 8-10 different days and drove the truck as normal. Could park truck for 3-4 hours and she would fire right up quick, as it was still slightly warm. Overnight parking and nothing again! When I was able to get the truck started cold there would be a bunch of white smoke coming out the exhaust stack before it fired up as I cranked, ...unburnt fuel right?

Now there is nothing flowing out the exhaust at all while I'm cranking the engine. Does that mean I have no fuel delivery and that's why it's not starting? Did my lift pump go bad in the process? I don't suspect the IP just because the truck runs killer when it does start. Pulled one injector that was leaking at the cap to inspect it and replaced o-rings and cap... put the injector back in and left the hard line off the top and the return line hose off.. got in truck and tried to start it as normal, a friend was looking to see if fuel was flowing out and saw that it was pumping out the return line hose but not down from the hard line from the IP... I'm at a loss and I know it's something simple, or at least I hope!!
 

Jesus Freak

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Do you hear the solenoid in the IP clicking. Turn the key switch to the on position, and unplug the wire on the top of the IP and then plug it back up. You should hear a click inside the IP. If you don't its the fuel shut off solenoid gone bad. Other than that, if you have a mechanical fuel pump, it could be bad. If the shower heads in the fuel cell have dicentigrated then you really need about a half tank of fuel for it to pick up. And then there's the screwed up fuel tank selector valve to consider.
 

Rdnck84_03

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@Jesus Freak you beat me to it. I was thinking FSS also.

@Baxter if you have had the the FSS and cold advance unhooked, make sure you didn't reverse them when hooked back up.

After making sure the 2 wires are plugged into the correct places, do the check Jesus freak describe. If no click testing that way unhook the FSS wire and hook a jumper wire to the positive battery terminal and touch the FSS blade. If you get a click that way you have an ignition issue. If no click the FSS is most likely bad.

James
 

Baxter

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Thank you both! Not with the truck at the moment but now I'm wondering if I cut that wire when I clipped the group of wires from the OE gp controller! I'll study that plastic loom and wiring when I get a chance ... does the FSS wire go directly to the battery? What is the cold start advance? I'll try to snap a pic of what it all looks like now so you can point out what's going on.
 

Rdnck84_03

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No the FSS is from the ignition switch. It would be powered the same way as the coil wire on a gasser.

James
 

Baxter

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hmmm ok interesting, still seems like I screwed something up when I disconnected the old controller. There was a wire from ignition to that stock relay of course... with that disconnected and going nowhere now I wonder if an old owner had tied the FSS wire into that wire so they didn't have to go all the way to the key or something I don't know ... I'm convinced it was when I wired up that manual switch kit I did something. kit is installed correct but my dismantle of the old.. screwed something up. thanks again!
 

Rdnck84_03

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The connector my finger is on is the FSS, the one directly behind it is the cold advance.

After looking at the factory harness I think I would be hard to reverse the wires. The wire laying over by the glow plug relay is the factory cold advance wire.

I am not sure where exactly the FSS wire is run. When I converted my glow plugs to manual control I just unplugged the controller and rolled the wiring up and zip tied it over by the blower motor.

James
 

IDIBRONCO

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a friend was looking to see if fuel was flowing out and saw that it was pumping out the return line hose but not down from the hard line from the IP.
You can hook a jumper wire to the pump on the spade for the FSS to do a quick check on whether or not it's working. If it works, then you know where to go from there.
The quoted part makes me think that it's just no power to the FSS and not the lift pump. If you're not getting power to the FSS and if the injector/return line is on the passenger's side, then your lift pump is still pumping fuel while the IP isn't. By turning the engine over with the starter, you're still making the mechanical lift pump work.
Not trying to be insulting here, but this is why I NEVER just cut away at wires until I know for sure that I don't need them.
 

Baxter

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You can hook a jumper wire to the pump on the spade for the FSS to do a quick check on whether or not it's working. If it works, then you know where to go from there.
The quoted part makes me think that it's just no power to the FSS and not the lift pump. If you're not getting power to the FSS and if the injector/return line is on the passenger's side, then your lift pump is still pumping fuel while the IP isn't. By turning the engine over with the starter, you're still making the mechanical lift pump work.
Not trying to be insulting here, but this is why I NEVER just cut away at wires until I know for sure that I don't need them.
thanks ok, that makes sense. And yes that was stupid idea to snip those wires even if they are now rendered useless. Never going to do that again.
 

Baxter

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The connector my finger is on is the FSS, the one directly behind it is the cold advance.

After looking at the factory harness I think I would be hard to reverse the wires. The wire laying over by the glow plug relay is the factory cold advance wire.

I am not sure where exactly the FSS wire is run. When I converted my glow plugs to manual control I just unplugged the controller and rolled the wiring up and zip tied it over by the blower motor.

James
Thanks for the pic!
 

Baxter

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Howdy I'm back with an update ... tested the FSS with key on, disconnected wire and reconnected it, NO CLICK. then ran a roach clip jump wire from positive battery terminal to the spade on FSS solenoid .. CLICK! so the FSS seems to be good right? please study pics ... sorry for this electrical wiring sh*t but here we go ... the wire(s) going to the spade on FSS is a double wire and it runs down to a weird plug into the block, and then one single small wire, (red) up that has been cut which I probably did when removing the OEM relay/controller somehow I think.. see it in the pic. (this is the suspect). I can only see 3 wires left from my cutoff when removing the controller... the bigger black one is just going nowhere to the drivers side glowplugs (old harness) the passenger side of the same gauge is removed as well as the big red power wire that ran from the battery to the relay/controller. this is what I'm left with. I tried connecting the two red wires together, NOTHING. then I did the same and grounded the smaller black wire, NOTHING. Please help if you see something here that I am missing, or a way to run a new wire from the FSS to ignition...?? Appreciate it!!
 

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Baxter

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mornin follow up! this thing is wracking my brain and I'm not great with electrical stuff ... is the best way to test that female end that connects to the pump solenoid, turn key on and ground a test light and touch the inside of the connector to see if it lights up? just want to double check if I'm getting power from key to the solenoid. I doubt there is any power in that wire now but ...
 

IDIBRONCO

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. the wire(s) going to the spade on FSS is a double wire and it runs down to a weird plug into the block,
That is your fast idle switch and only affects the fast idle solenoid and the timing advance. Even if that doesn't let power through it, for some reason, you should still be getting power to your FSS. That's assuming that you have an original, unmolested (uncut) wiring harness.
. is the best way to test that female end that connects to the pump solenoid, turn key on and ground a test light and touch the inside of the connector to see if it lights up?
Yes.
 

Baxter

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I thought this spade was the FSS power coming from the ignition ... see pic. the one behind it is the high idle connector correct?
 

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