"85 GTI Wiring Diagram

[Toby]

I am in need of a wiring diagram for my Low Buck GTD project. The car is an '85 GTI and I need to identify some wires in the harness. I have cleeved the harness asunder to remove the unneeded CIS-E, OXS, and ignition wires. Now I need to identify the wires that run to the tach, fuel pump relay, and OXS light, which I plan to use for a glow plug light. I have a bunch of wiring diagrams for the generic '85 Golf but they are a bit vague and do not clearly identify what it what and none show the tach circuit. Does anybody know where I can lay my hands on a GTI wiring diagram short of buying a Bently manual?

[CRSMP5]

working hard huh...

tach/pump is red/black at coil.. usually hooked w a greenish wire.. thats the wire you seek to splice into for w

other side of coil black hot w key for fuel pump..

the goofy box the speedo cable goes thru by the rad bottle.. thats the oxs box.. the glow plug light wire you seek is there.. unplug and tap right in.. color no idea.. but that box used on lots so id get a "pin out" of it for what terminal the light is.. think its 3 wires.. been too long..

[Toby]

That is the problem. There is/was no red/black wire at the coil. Only the green, (now gone) and the yellow (12v). In addition, there is no OXS box on this car. Clearly the GTI wiring is different than what I am seeing on the Golf wiring diagrams. I just went and looked at the door sticker and it has an 11/85 production date, so it is really an '86. The only red/black wire that I see is a heavy wire down near the starter. Perhaps the starter solenoid wire (red/black) splits in the harness. I will have to pull it out of the plastic tube and look. Still need the GTI wiring diagram, though

Fore the glow plug set up, I took a late Ford solenoid and affixed it to the bracket that supports the multi pin plug at the front of the motor. The 2 extra studs are just the right distance apart to bolt the solenoid up between the water outlet on the end of the head and the #4 glow plug. That will give me a sano short run from the starter to the fuse, then to the solenoid and 4" to the bus bar. I may hook the glow plug cable to 3# instead of #4.

[CRSMP5]

 gti = knock sensor and westy built.. so not german..

forgot that,... 85 german jetta better had that to look at..

how id do it.. instrument cluster harness.. the tach wire in it needs spliced in.. just add a w wire there and the oil pressure lights and all should work...

since it goofy westy.. find the instrument cluster plug in the harness down by fuse block.. remove its pin and commect to a w wire.. it is nothing like ce2 or other german set ups..

hmmmm no oxs box... hmmmmmmm did they...

i guess id do it easy.. pull cluster.. black sharpie... follow the trace thru the pcb and see which wire in the plug for both tach and gp light..

that plug should be same on german ce1 mk2 stuff... so looking at say jetta harness may help.. wire may be different color.. but plugs in same on cluster..

[Toby]

gti = knock sensor and westy built.. so not german..

forgot that,... 85 german jetta better had that to look at..

how id do it.. instrument cluster harness.. the tach wire in it needs spliced in.. just add a w wire there and the oil pressure lights and all should work...

All the other stuff is functional. There is a tach wire in the harness that went to the coil or controller. I just need to find it.

since it goofy westy.. find the instrument cluster plug in the harness down by fuse block.. remove its pin and commect to a w wire.. it is nothing like ce2 or other german set ups..

I am not using the W wire set up. I intend to set up a magnetic pickup in the timing hole to be triggered by the 2 lugs on the flywheel. The are close together but should give 2 strong pulses per revolution.

hmmmm no oxs box... hmmmmmmm did they...

i guess id do it easy.. pull cluster.. black sharpie... follow the trace thru the pcb and see which wire in the plug for both tach and gp light..

All that I need to do before I light it off is find the FP relay wire. The tach can wait. I would just like to identify the wire so I can button up the harness. I have found a plug that may have gone to an OXS box that was long ago removed.

[bajacalal]

I have a Benetley and a scanner large enough to do two pages of it at once. I could maybe email some to you.

You should really get a Bentley manual though, if you deal with multiple Volkswagens, as mine covers everything mk2 gas or diesel, it's a great problem solver and they're less than I think they used to be.

[Toby]

If you could scan the '86 GTI stuff and email it to me, I would certainly appreciate it. I have half a dozen Bentley manuals for both VW and Audis, just no Mk2 examples. I think I have all of the important stuff figured out, but there are a pair of wires that, as yet, I have not identified. They are long, so I may just leave them for a future, as yet, undetermined use.

The Tach wire is Green/Blu.
The FP relay wie is Br/Yel.
The OXS light wire is Tan/Red.
B+ is Yellow or Yel/Blu if fused at F22.

The OXS light is on with Tan/Red grounded so I will need to modify the cluster by grounding what is nowthe hot side of the LED. That way I can tie it to the bus bar so I have an actual indication of 12V to the GPs instead of just the relay calling for GPs which may or may not have voltage. I also tied the power lead to the bus bar at #3 instead of #4 so the current path in the bus bar is reduced. Not that it will make any difference, but I ran out of my OCD meds!

If I have the FP relay wire correct I will light my LB GTD off in the AM. Still need a way to tie into the exhaust and some kind hose and filter for the turbo intake. Somewhere I have/had a cast aluminum pipe from a SAAB or Volvo Turbo that has the right 90* bend and may even flair out enough to take a cone filter. It even has "TURBO" cast into it. Now if I just refrained from pitching it in with the last load of scrap I sold.

[bajacalal]

I recognize that as a SAAB part.

But honestly, I would not use it.

It's not very well designed for forced induction use. The diameter is small. It's rough cast aluminum, so the inside is kind of ragged. The bends are sharp. Basically, it's restrictive to the flow of air. You would do better with something like mandrel bent tubing.

[Toby]

What you say is certainly true. I am just looking for something to use for an air filter before I light off the motor,