Glow plugs drivin me crazy

[LCAM-01XA]

So a solid ground on the white terminal? Sorry I'm not typin much response I'm on a damn I pod touch lol

NO! White wire is what the controller uses to ground the trigger circuit of the relay, do not eff with the g/d white wire! lol

Seriously tho, the ground you need to be chasing on my truck was a black wire that came out the back of the controller (same place where the other wires came out of) then ran to a stud on the intake manifold. In Goofy's truck the wire is apparently brown in color, and runs to one of the bolts that hold the controller to the intake.

 

[Goofyexponent]

Exactly. The controller needs to ground as well as the relay.

I would check that brown/black wire on the controller box for a solid ground and go from there.

 

[BugEyeLights]

I am having the same problem with my 94 idi turbo. I need new connection boots for the glow plugs (having a hard time finding them, going to check with a International Dealer today.) I put new Autolight glow plugs in a week ago. Anyone had problems with Autolight glow plugs?

 

[Agnem]

Originally Posted by Agnem
Have you done the contactor test yet? Place a test light across the heavy lugs on the relay.... should light when truck is off, and should go out COMPLETELY when relay is energized.

Which lug do i test?

Um... there are 4 things on the top of the relay. Only 2 I would consider the "heavy lugs". There is no such thing as a good relay. It's like an airplane. A good landing, means you get to use the plane over again. Same with a good relay. Kapish?

 

[LCAM-01XA]

Exactly. The controller needs to ground as well as the relay.

See, this is where you're confusing him - for the relay to work its trigger circuit needs a ground, yes, but in case of the solid-state controllers this ground path goes through the white wire, then through the controller, then through the brown/black wire, and ends on the intake plenum through a bolt somewhere. The moment you give the relay its own ground is the moment you will fry all your plugs.

I am having the same problem with my 94 idi turbo. I need new connection boots for the glow plugs (having a hard time finding them, going to check with a International Dealer today.) I put new Autolight glow plugs in a week ago. Anyone had problems with Autolight glow plugs?

Get those Autolites out of there, ASAP. What you should be using is Motorcraft/Beru, model nuumber for your truck is ZD-9. Autolite and Motorcraft is not the same, in my experience Motorcraft parts have always been better than Autolites, and in case of glowplugs the difference can be the one between simple glowplug replacement and pulling the heads off the engine.

 

[MidnightBlade]

I am having the same problem with my 94 idi turbo. I need new connection boots for the glow plugs (having a hard time finding them, going to check with a International Dealer today.) I put new Autolight glow plugs in a week ago. Anyone had problems with Autolight glow plugs?

replace all 8 autolites right now! as for the terminal connection i went to a hardware store and got 8 heat shrink female bullet connectors, take a glow plug with you to make sure it will fit nice and tight. the wire to the glow plugs is 14 gauge. cut the old connectors off and pinch these on. you will need to tirm some of he shrink stuff off the end that connects to the glow plug, and only shrink the end that goes to the wire.

and David, till winter is over and your not freezing your kahonies off, just use the hair dryer again

 

[franklin2]

The above diagram is not correct. The red wire does not go to the ignition. The red wire is jumped over to the yellow power wires. The power is on the relay all the time, but does not energize the relay unless the controller grounds the other side(the white wire).

I have also heard of a ground wire leaving the assembly that is important for it to work. If you think about it, how would the controller "ground" the white wire if the controller didn't have a good ground to use? The "brains" in the controller would also need a good ground so it will get power enough to "think" and work correctly.

Of course you all know what I would do with this mess, but I don't want to sound too much like a broken record.

 

[Goofyexponent]

The above diagram is not correct. The red wire does not go to the ignition. The red wire is jumped over to the yellow power wires. The power is on the relay all the time, but does not energize the relay unless the controller grounds the other side(the white wire).

I have also heard of a ground wire leaving the assembly that is important for it to work. If you think about it, how would the controller "ground" the white wire if the controller didn't have a good ground to use? The "brains" in the controller would also need a good ground so it will get power enough to "think" and work correctly.

Of course you all know what I would do with this mess, but I don't want to sound too much like a broken record.

Post removed by me due to improper diagram. Sorry for the screw up.

 

[dyoung14]

Um... there are 4 things on the top of the relay. Only 2 I would consider the "heavy lugs". There is no such thing as a good relay. It's like an airplane. A good landing, means you get to use the plane over again. Same with a good relay. Kapish?

Ok i put a voltmeter on the lugs, black end on the z strip lug red end on the lug with the yellow wires, show 12.14 volts with the switch off turn it on and i get 12.04 volts

 

[OLDBULL8]

THE RELAY IS SHOT. GET A NEW ONE. SIMPLE AS THAT.

 

[Goofyexponent]

THE RELAY IS SHOT. GET A NEW ONE. SIMPLE AS THAT.

I agree in saying that the relay is *****-ed.

Just because the relay is clicking, closing the loop, don't mean that it's supplying enough power. It might have been on it's last legs when it was "known good".

I have had the starter solenoid (fender mounted, and the same part * IIRC) go bad in the F150 I had. When I replaced it (after cursing and swearing a lot), the truck took right off.

The solenoid was clicking like it should have, but not enough contact was left to make the truck start. I think this is what is going on with yours.

If you get in the truck, turn the key on, the GP light comes on and goes right out within 1 to 3 seconds or so, right?

That sounds like a bad contact within the relay.

 

[Agnem]

Exactly the reason I recommend this test. We discovered the need for this at the 2008 IDI weekend with Gary's truck, as we tried to cobble together a good GPC for him. We put a brand new relay in it, and within a few starts, it failed this test. I opened it up to find out way, and saw how cheaply it was made. Also, and this is a little tid bit for you.... let's pretend you are at an IDI Weekend, and you are a contest judge looking at a 93' F-350. You need to check the milage on it, so you turn on the key for a second or two, just long enough to let the odometer light up. DO NOT DO THIS!!! WAIT.... for the wait to start light to go out, before you turn off the key. WHY? Because - the glow plugs draw a ton more amps when they are cold, then when they are hot. Opening the contacts on the GPR with cold plugs will create a LARGE arc, pitting and damaging the contacts. If you wait for the plugs to come up to temp, they will be drawing a fraction of what they were when the contacts open, and you will extend the life of your relay.

You must be registered for see images

 

[Goofyexponent]

Exactly the reason I recommend this test. We discovered the need for this at the 2008 IDI weekend with Gary's truck, as we tried to cobble together a good GPC for him. We put a brand new relay in it, and within a few starts, it failed this test. I opened it up to find out way, and saw how cheaply it was made. Also, and this is a little tid bit for you.... let's pretend you are at an IDI Weekend, and you are a contest judge looking at a 93' F-350. You need to check the milage on it, so you turn on the key for a second or two, just long enough to let the odometer light up. DO NOT DO THIS!!! WAIT.... for the wait to start light to go out, before you turn off the key. WHY? Because - the glow plugs draw a ton more amps when they are cold, then when they are hot. Opening the contacts on the GPR with cold plugs will create a LARGE arc, pitting and damaging the contacts. If you wait for the plugs to come up to temp, they will be drawing a fraction of what they were when the contacts open, and you will extend the life of your relay.

You must be registered for see images

That is just what I was trying to say, but Mel hit it right on the head. Great pic for reference too!!

Just because something is new, or worked just fine don't mean it will when you need it to lol....Murphy's law.

 

[LCAM-01XA]

The above diagram is not correct. The red wire does not go to the ignition. The red wire is jumped over to the yellow power wires. The power is on the relay all the time, but does not energize the relay unless the controller grounds the other side(the white wire).

Nope, you are wrong, and the diagram is absolutely correct. I know this for a fact, as my manual switch (works by grounding the relay instead of the white wire) is only capable of triggering the relay when the ignition is on.

Also, think about it - since the red wire for the controller comes off the relay terminal, if the other red wire is jumped off the yellow constant-power wires then that would mean that the controller has power to it all the time as well, then how in the world will it know when the ignition is turned on? I know what I see, and what I saw on my truck is a red/green wire coming out of the harness behind the engine and going to one of the small terminals on the relay, then there was another wire of the same colors that left the same relay terminal and went down into the controller box under it - both wires had factory ring terminals on them the kind that I have never ever seen in a hardware store, and you need a special tool for them anyways. Not to mention that I have measured the voltage on these wires, and it is only there when the ignition is on. If you wires up your relay so its trigger circuit is hot at all times that is one thing, but the factory setup is notthing like what you describe.

 

[LCAM-01XA]

Ok, All fixed. The reason why I have the red wire as ignition is because mine is wired 12 volt ignition. My truck was a wiring nightmare, so this is the fix I chose, but it's good to know how to wire it correctly.

You must be registered for see images attach

Remove this diagram, it is not correct - your first one was the correct one. Also, on both diagrams you forgot one wire - it's a red/green wire that connects to the same terminal of the relay as the red/green wire you already have on the diagrams, but its other end is inside the controller - this wire is what turns the controller on when ignition is turned on.