Dielectric grease applied to both ends of ignition wires

[dukbludvl]

So, I'm a moron. It's been years since I've changed plugs and wires. This week, I installed new Delco platinum plugs and new Delco wires on my 2003 GMC Yukon 5.3L 2wd with Delphi coils, about 150k on the motor. Everything went well with getting the old plugs out and new plugs in. Then, I went ahead and installed the new ignition wires and mindlessly glopped a bunch of dielectric grease on BOTH ends of the ignition wires before putting them on, thinking it would help with conduction and not act as an insulator.

I should have known right away that I effed that up because I figured I'd fire up the engine and she'd be smooth and happy. But, it was actually a little hard to start then it wanted to stall. I drove it around some -- ran in to work and back to the house, so maybe 30 miles round trip, with a couple stops in the middle. It idled rough, but otherwise ran fine most of the time -- no ticks, knocks, bangs, and seemingly no misfires, but maybe I missed some misfires? It did stall on me a few times when I started it and tried to put it in reverse to get out of a parking space.

Anyway -- need your advice. How do I undo this mix-up? My plan is this:

A. Remove these wires with all the grease in them and put on a totally new set of wires with only a thin coating of grease applied with a Q-tip to the boot only -- and not to the conductive metal/wire ends inside the boot.

B. Wipe the grease off the plug terminals that the boots were installed over as best I can with a paper towel.

C. Take a Q-tip and try to wipe the grease off the inside of the coil boots/connectors, and wipe the outsides of the coils with paper towels to try to get all the grease off as best I can.

My questions are these:

1. Any other suggestions about how to get the grease off the plugs so it won't interfere with the conductivity of the plugs? Is wiping it off sufficient, or should I replace my new plugs with another set of new plugs?

2. Have I permanently damaged the Delphi coils by essentially cramming grease up them from pushing the wires on? Do I need to replace my coils?

3. Anything else you all recommend?

Thanks in advance for your help on this. I just want to get my Yukon back running right again. The stalls and rough idle had me freaked out for a bit.

Jon

 

[mb1500]

If you’re making good contact I would think that the grease would be irrelevant. Go ahead and clean up what you can as far as the grease goes and see what happens.

 

[OR VietVet]

A glob is never needed, just a very thin film and I really don't see the grease causing a problem. Pull the wires and clean up the plug tips and and use the Q-tip to clean the excess grease at the wires and again, very very thin film is all that is needed. I would think that you should have set a misfire code and recheck that plug to make sure you did not crack it during install.

 

[wjburken]

I like to put a little on an old plug and push the old plug into the plug wire just to get a nice thin coating prior to putting it in the new plug. Just like the old brylcreem commercial-A little dab will do ya!

 

[Fless]

If your electrical connections are good, the dielectric grease gets displaced by the contact. It displaces air that corrodes contacts. So I'd be looking for a contact problem, maybe a wire that's not snapped on all the way or is broken.

If it bothers you, remove as much of it as possible but a little isn't going to hurt the electrical connection.

 

[OR VietVet]

Dielectric grease, or tune up grease, is a silicone-based grease that repels moisture and protects electrical connections against corrosion. It is also used to keep dirt, water, and other elements out of electrical connections. It has many uses, including automotive tune-ups, home electrical work, and recreational vehicle wiring. Dielectric grease does not dissolve in most liquids, so it is good for marine and outdoor applications. You can use this grease to lubricate the rubber parts of electrical connectors, spark plug wires, and to protect electrical connections on your boat or recreational vehicle from corrosion. Since dielectric grease is a silicone grease, it should not be used on silicone-based rubbers or plastics, as it will break them down over time. The grease does not conduct electricity, so it shouldn’t be applied directly to the mating surfaces (pins and sockets) of an electrical connection.

How to Use Dielectric Grease
To use dielectric grease during an automotive tune-up on a gasoline or diesel engine, apply a bit of the grease to the end of the rubber boot on a spark plug wire and spread it around so it is just covering the inside of the lip. This will prevent high voltage electricity from traveling inside the boot and “leaking” out into the engine block. Additionally, the dielectric grease will make it easier to slide the boot over the ceramic insulator on the spark plug and ensure that there is a water-tight seal around the plug that will protect the connection from water and dirt.

You can also apply dielectric grease to the gaskets on multi-pin connectors that are typical in the electrical systems of boats and recreational vehicles. Simply take a small dab of the grease and smear it around the gasket on both sides (if possible) before inserting the gasket around the connection.

Dielectric grease can also be applied to the metal parts of virtually any electrical connection that will be exposed to the elements to serve as a sealant that protects the connection from contamination and corrosion. This should be done very carefully, as the grease will cut off the flow of electricity through the connection if some of it is left between the mating surfaces. As always, we recommend working with your local auto mechanic when doing any maintenance on your vehicle.

 

[Fless]

Eric O shows how he does it (the link starts at the wire install):

EDIT: put a scan tool on it and check for misfires.

 

[FrankU]

I have used Dielectric grease many times over the years on lots of vehicles and never had any kind of problem.

I'd ohm out the spark plug wires while rolling or shaking them between your fingers.

Check spark plug gap. Or even look at the secondary voltage under the hood at night to look for arching.

Good luck

 

[Big Mama]

Yeah, sounds like at least one connection is amiss more than the grease causing problems.

 

[Fless]

I wanted to ask if you gapped the plugs, and at what gap? The platinum and iridium tipped plugs can be damaged if not gapped properly, although most times they're pre-gapped and don't need to be changed.

Any other work done at the same time? All electrical connectors reinstalled?