Energizing Glow Plugs

Hi All,

I have a 1997 Tdi which suffered a lot of electrical damage when the main electrical harness made contact with the fan. I have put the car together as best as I can, although the VSS does not work (I use a GPS speedo) and the coolant temp sensor does not work (i installed an aftermarket coolant temp gauge).

I do not believe the glow plugs are cycling at all. The glow plugs are all new Bosch and the car has trouble cold starting at around 40 deg F, although it would usually start. On a few nights, it froze and I started around 32-35 deg F in the morning and it took several tries. The engine otherwise runs like a champ. The IP timing is good and verified by VAGCOM.

My plan is to eventually swap the engine into a Samurai, but I need to get a bunch of pieces together first.

I am looking to put together a push-button to manually energize the glow plug relay. I have seen a thread where this was done (http://forums.tdiclub.com/showthread.php?t=264313), but I'm not seeing enough detail to give me the confidence to start cutting into the wires.

Has anyone done this? It would be good to start with other documented projects if there are any.

Just to be clear: my OEM setup is completely FUBAR. I have already spent *a lot* of time and money and talked to a bunch of experts to fix the OEM setup. When the car starts, it runs just fine. I have already driven it cross country and put on a lot of miles like this.

Thanks,

h.ubk

I'm beginning to think that thread is needlessly complicated.

After doing some research, this is my understanding. I would appreciate any correction.

If I can find relay 180, there should be two high gauge wires and some lower gauge wires. If I strip the lower gauge wires, I can find ground with a test lamp and leave it alone. From there I just need to find the energizer wire and wire my switch into that.

Is this correct? If so, the million dollar question would be which wire is that? Does anyone know the color combination?

Thanks,

h.ubk

a "bunch of experts" huh? ...i can't imagine your factory glow system being so beyond repair that it can't be fixed... especially when the car still runs and drives... fix the temp sensor and rewire the glow plug module... you're adding complication and hassle by seperating this system from the engine controls... unless you plan on ditching the e pump for a mechanical setup in your swap, figuring out the glow system will be a tiny hurdle compared to the rest of the harness

Funny when you look at my OP on the topics, NOBODY has anything to say about it. I'm not going to rehash it. The previous owner had the car at the dealership and a local VW guru. My mechanic also had a local VW expert look at it a few times. The bottom line is the electrical diagrams in the Bentley are incomplete and nobody can explain how the coolant temp sensor is supposed to get 6V from the ECU. The old wiring harness is fried. The PO tried to have it repaired in place by a shop. It was replaced by a used, "supposedly good" harness which didn't fix any of the problems. The local VW expert wanted $1000 to pull the harness and test it. There is likely secondary damage from the crash in a number of areas.

How exactly should I fix it when NOBODY has any answers in person or online except to junk the car? It's funny how everyone is a keyboard expert until they have to actually look at the problem.

h.ubk

keyboard Experts?....Hmmm

I'll address your original question, and then.

Use a ford starter solonoid to energize the glow plugs. Use a push button in the engine compartment to trigger the solonoid...problem solved.

If the CTS is supposed to get 6v from the ecu, it comes from the ecu, that simple.

I think part of the problem here is the way you are presenting the info. You state i the first post that the main harness came in contact with the fan. Not until last post do you mention a crash.
It seems you have had the misfortune of dealing with people that are not at all familiar with your car. The harness in a mk3 is modular. The down side is the lighting harness is packaged with the engine harness un like a b4. There is no main harness in the engine harness. Everything goes through the fire wall and plugs into the fuse box under the dash.
This is one of the most simple wiring systems (ce2) to work on. Forget the Bently it will drive you nuts.
Are you having problems with any of the lighting? As stated, it is part of the same harness. The way it sounds I would think there are issues here also

Use a ford starter solonoid to energize the glow plugs. Use a push button in the engine compartment to trigger the solonoid...problem solved.

Click to expand...

Are you saying to pop the hood every time I need to manually glow the plugs?

I think some of the people who have seen the car do know an MK3 quite well. I could name some names, but I'm not going to. The last owner *loved* this car and did everything he could to save it. The ECU has already been out of the car and tested by a reputable shop by the PO. The voltage needs to flow through the harness circuit to get to the CTS which it is not. The Bentley does not have a diagram of how this works, and yes it is almost worthless -- a lot of the info pertains to gas cars or is not listed or is listed wrong for my car.

I'm sure a lot of it is fixable by some guru, but the point is mute since the amount of labor needed greatly exceeds the value of the car. I would never have bought this car except for the low miles engine to do the swap. Since I can use mechanical instrumentation on a Samurai, it doesn't matter much if this gets fixed properly. I have had several other diesels, and I absolutely *hate* this stupid VW computer control stuff on a simple mostly manual controlled car. IMO, the only thing I need the ECU for is the IP as I am not going to an mTDI. I'm perfectly capable of deciding how long the glow plugs need to glow and I do not want the computer to override my own decisions.

Are you having problems with any of the lighting? As stated, it is part of the same harness.

Click to expand...

Nope, no problems at all with the lighting. I had Derek (Chub's Auto) rebuild my instrument cluster which was fried from this incident. I believe the main wiring harness is actually fine, but there is secondary damage somewhere or in multiple places from over-voltage like the cluster. My mechanic wants to replace the fuse panel and says there is some corrosion there. Bottom line is that testing all of these components individually and then as a system is a phenomenal amount of work.

h.ubk

Sorry I mis-spoke. Put the pushbutton in the the trunk. It IS possible to run a wire to almost anywhere needed.

I think there is something missing in this equation.