How to make a $2 glow plug harness.

another sucuessfull $2 glow plug harness. Well mine cost just a little more.
slide on connectors like shown above (but NOT shrink tube) $1.97
3/8" plastic slide on tubing $1.99
Assortment of Shrink tubing $1.97
I already had the wire and solder.

I used 12 gauge solid wire to make the 2 loops for the glow plug pairs.
I use 12 gauge stranded wire to run from the 2 loops to the factory harness.
I used what ever that stuff is you buy from Home Depot to stop corrosion on Aluminum electrical wire on the glow plug ends.

When I first started the car, I still had the glow plug light so I added a little loop that connects the 2 feeds from the factory harness. I started car again and still had the glow plug light. Hooked up VCDS and cleared code, glow plug light has not been on since. (I guess glow plug light was coming on because of memory of code?)

Anyway, started car at 24deg Christmas morning, started perfect with no stumbling.

I wanted to bump this and see if anyone who was using the homemade set up is still running with no problems. I guess the circuit has a 60A fuse so using 14g wire would definitely keep me awake at night, but I guess the factory wires can't be much bigger.

Of course it's summer now, but mine is still working fine. Why not, its actually heaver then the factory one .

In fact I even forgot it was on there until I read this thread.

https://www.google.com/search?q=hea...GKPo6gHPsuXCCg&ved=0CIsBEK0E&biw=1024&bih=585


Heat shrink butt connectors. I used them every now and then. They work well as long as the wire you're crimping is the right diameter and not too small.

Bump!
Just found this. Going to build one to clear CEL. Home Depot sells NOALOX Anti-Oxidant in the elecrtical section. Small .5oz tube will last FOREVER in the small amount needed.
I used the NOALOX to help clear fault code. It worked, but 2 days later while replacing vac lines I pulled and accidently got caught on the harness.. breaking a connector .

Thanks for the idea. Going tonite for parts.

Rual817 said:

Bump!
Just found this. Going to build one to clear CEL. Home Depot sells NOALOX Anti-Oxidant in the elecrtical section. Small .5oz tube will last FOREVER in the small amount needed.
I used the NOALOX to help clear fault code. It worked, but 2 days later while replacing vac lines I pulled and accidently got caught on the harness.. breaking a connector .

Thanks for the idea. Going tonite for parts.

Click to expand...

I used 4 female bullet connectors (fit perfect on the GP's), 12ga. wire, 3/8" universal wire conduit, and 2ea. male/female spade connectors to attach to main line. Coated all connections with NOALOX, and wrapped conduit with elec.tape. Worked great!

bump

seeing lots of Harness issues

Yep, it is getting to be that time. We are going to be seeing lots of these, as well as broken/cracked vacuum lines, broken/cracked fuel return line, parking brake cable corrosion, paint peeling from the rust underneath, broken plastic parts of all kinds, worn tie rods, dying rubber bushings, bearings, wires breaking where they go from the body to a moving part (i.e. trunk lid, hatch, doors) etc. etc. etc. as the MkIV cars age and show it. Belts and fluid changes aren't the end of maintenance, as everyone well knows.

So it will become either maintenance time, or sell it and buy another car time. I prefer the maintenance myself. It's cheaper, and I'm a tight-wad. And there's a bit of satisfaction received when problems are resolved in my favor for a reasonable cost.

Is there a place you can buy the connectors that go to the glowplugs themselves (Basically the ends of the GP harness).. I'd much rather fix my harness then drop $60 for a new one from VW.. But a few of the connectors have snapped completely off.

LNXGUY said:

Is there a place you can buy the connectors that go to the glowplugs themselves (Basically the ends of the GP harness).. I'd much rather fix my harness then drop $60 for a new one from VW.. But a few of the connectors have snapped completely off.

Click to expand...

Yeah but the connectors are almost $40 each.. part number 028 971 782A is just a glow plug end and a few inches of wire.. much cheaper to just get the OE harness for $60 or run some 8-32 threads on the glowplugs and bolt the wires to them.. works like a charm..

TDIJetta99 said:

...run some 8-32 threads on the glowplugs and bolt the wires to them.. works like a charm..

Click to expand...

This is the way to go, I made mine ~5 years ago and wired all the 4 wires together so the ECU will always see the same voltage back from every GP, I have had one GP code since and it was when 2 GPs had failed so the voltage was wrong for all 4 GPs, according to the ECU. Its perfect really, the car starts fine with one GP bad, but with 2 bad its not too happy in cold weather. I replaced those 2 GPS and no codes since.

Please excuse the filthy engine, I missed the dirt by the number 1 and 4 injectors.



And here you can see the lump in the wires, that is where I stripped the insulation and wired all 4 wires together and hit it with the soldering iron and solder,

TDIJetta99 said:

Yeah but the connectors are almost $40 each.. part number 028 971 782A is just a glow plug end and a few inches of wire.. much cheaper to just get the OE harness for $60 or run some 8-32 threads on the glowplugs and bolt the wires to them.. works like a charm..

Click to expand...

Ahhh... so that's the clincher, lol.. Looks like a new harness is in my future.

Appreciate the info!

koolpunjabi, I took the liberty of making a .pdf of your instructions. Hope that's OK.

How To Make a $2 Glow Plug Harness
By: koolpunjabi

http://pics.tdiclub.com/data/500/How_to_Make_a_2_Glow_Plug_Harness.pdf

.

Wish I had seen this one week ago!

My 02 TDi has had a defective GP harness for 6 years. NYS just required light duty diesels to have CEL off in order to pass state inspection since 07/2012, so I had to get this fixed. I went through heck (worse really)to get the right harness. The dealers kept using my VIN# to order the harness, and I kept getting the 2 wire harness instead of the 4 wire harness with the long wires and the single connection plug. Turns out, my 02 TDi Bug, built in 04/2002 has the harness that goes w/ the 2003 vehicles! Anyway, the correct harness has been ordered and should be here today, or I would make one myself! I'll keep the old connectors from the old harness just in case.......

Hah! New one just arrived! Time to get to work!

Has anybody made a harness for a PD? To recall, I read someplace that the PD's use a 4 wire harness.

LNXGUY said:

Is there a place you can buy the connectors that go to the glowplugs themselves (Basically the ends of the GP harness).. I'd much rather fix my harness then drop $60 for a new one from VW.. But a few of the connectors have snapped completely off.

Click to expand...

TDIJetta99 said:

Yeah but the connectors are almost $40 each.. part number 028 971 782A is just a glow plug end and a few inches of wire.. much cheaper to just get the OE harness for $60 or run some 8-32 threads on the glowplugs and bolt the wires to them.. works like a charm..

Click to expand...

Basic bullet connectors prob $5 for 20 fit over the GP.

I figured he was talking about the OE connectors.. The bullets work fairly well but tend to have the same connection issues the stock ones do..

Anybody on my PD harness question?

Be the pioneer and try it.. I haven't had the opportunity to do one on a PD yet..

Well, good point! And if the harness isn't any good I don't really have anything to lose! But, I have a cpl other priorities like a cv joint that's in real bad shape. When I do it ill post back with what I learn.

Bringing this back to the top! Thank you so much for the write up when i got the car i had 2 glow plugs that were not even connected because of the messed up wire harness.
replaced one glow plug and made a new harness out of extra solid 12awg wire (i just ended up twisting the wires up very tightly with pliers and heatshrinked it no solder but followed the rest)

thanks again and i did not see this on the How To list. should be there

Thanks!

Thanks for this! With the weather turning cold I got glow plug codes but all plugs checked out fine. Just completed the harness with 12 guage wire. Used black wire, black sheathes/conduit, and blue connectors. I think it doesn't look too bad really. PD engine.
The down side, I lost track of which cylinder # is which, lol


And if anyone is wondering, these connectors also fit perfect on the coolant glow plugs.

great idea! before I start this project I thought I'd ask - the problem seems to be where the harness fastens to the GP. is it possible to just remove the hard plastic from the harness and reuse the existing wire after installing new/better ends?

powerchoke said:

great idea! before I start this project I thought I'd ask - the problem seems to be where the harness fastens to the GP. is it possible to just remove the hard plastic from the harness and reuse the existing wire after installing new/better ends?

Click to expand...

Yep! That's what I've done. But, they will be exposed to the elements. You should also clean the connection (top of GP and fastener) for good current flow!

This is a great DIY project. My 99 got to the point where it just crumbled. The boots were cracked and brittle, connects were great, so a bit more than $2, but a good money saver.

I'm impressed by the bang for the buck here. Hopefully I can find a way to get it as well.

Just to update this, there are two common sizes of bullet connectors, 0.157" and 0.176".

The 0.176 connectors don't fit our glow plugs.

I also found that Dorman makes a heat shrink version of the 0.157" ones, p/n 85268, which is available at AutoZone among other places.

(Now to finish building my harness, with the smaller ones that don't fall off the plugs...)