Protecting Connectors on the Glow Plug Harness

It seems that the glow plug harness is the root of many TDI evils, and it could be a cause of some of my problems.

It seems that the glow plug harness connectors can't be cleaned, and the only option is replacement.

Has anyone attempted to coat the glow plugs/fill the connectors with dielectric silicone grease (or just plain old grease) to ward off harness terminal corrosion?

When I inspected my electrical contacts, I noted that there wasn't any grease in there.

When I replaced the alternator harness on my 87 Ford F250, the replacement came with a generous amount of silicone grease, and I have also always greased my battery terminals and taillight sockets to ward off corrosion. Spark plug boots, too.

The only reason why I haven't greased those glow plugs is because of the engine computer, and I do not know what (if any) the effects may be.

Yes ... in fact just this weekend I replaced all four of my glow plugs (67K miles) because one was reading infinite resistance. I used Ox-Gard on the harness and on the plug terminals. Ox-Gard is a corrosion inhibitor plus a conductivity enhancer, which is what you want for the high resistance sensitivity of the connection. Silicone grease, while inhibiting corrosion, will do nothing to enhance conduction and could, in fact, actually insulate parts of the connection.

I read on here somewhere that VW recommends Stabilant 22A be applied to the joint. Stabilant 22A is a conductivity enhancer and a corrosion inhibitor ... you can purchase a 15ml kit at NAPA auto parts for a mere $60. /images/graemlins/eek.gif

That's why I chose to go with the Ox-Gard. $5 for a 5 oz tube of the stuff at Lowes (or Home Depot) in the electrical section. I also use this stuff on other connections like light sockets. /images/graemlins/grin.gif

I agree. Plus, cheaper is better.

Yeah, but has anyone addressed the question raised a few days back:

Is there any difference between dielectric grease and Ox-Guard?

Do you know what 'dielectric' means? Have you ever used it, built an electrical device that used it? Dielectric means insulator! It means nonconductor! It is properly used as a heat transfer agent between IC and their substrate to allow them to run cooler by dumping heat to the sink. And I'm not yelling at you but at the selfsatisfied know-nothings that post here as experts. "Mailman' said all that should need to be said about Ox-Guard. I too use it on lamp bases.

Thanks for the info on the Ox-Gard... never heard of it. I'll have to look it up the next time I am at the Depot.

I have never had a problem with conductivity using the dielectric grease, but I have never tried it on something that an automotive computer is capable of diagnosing.

Has anyone successfully cleaned those harness contacts, maybe with some type of solvent?

Hey guys, I'm not Mr. Mechanic when it comes to cars, but on aircraft avionics we use a White Lithium grease after cleaning it with contact cleaner, just don't go hog wild with the stuff, light coat is fine, even petrolem jelly will work, too much = more resistance, just enough to keep moisture out. Contact cleaner won't work if contacts are corroded, than they will need replacement. I was snopping around http://www.vwparts.com and found a NEW STLYE glow plug harness ON SALE for $35.01 in which it contains connectors instead of splices. Here is the part number, this looks like an anwser to our prayers! part number: 038971220C. By the way, what did you guys get for resistance figures on your glowplugs? I found 3 to be around 0.6 ohms and one to be around 197.30 ohms, I guess the ladder one is the bad one. Thanks guys!

That's about what I had: 0.5 on three of them and 50.7 on one of them.