Haner

You know, I've been wondering the same thing. And it seems you and I are the only ones in the world that have it. I've gotten no help from anyone on this site. Either they don't have the same parts, or they don't have the problem. I guess there just aren't that many 90s on the road these days. Too bad, cause I just turned 300,000 miles last month on the same 350. I had the tranny rebuilt, but the motor is still goin' strong.

Try the grease. I'll bet it works.

8k15009

I have the same problem on my 89 K1500. Crazy wipers randomly pulse, run after turning them off, park anywhere and the washers don't work. I replaced the washer pump and it worked for about a month and quit. I'm thinking there must be an easy fix since nobody is responding.

Haner

Try the fix I describe in this thread. It continues to work for me. I know it seems too simple, but it's still working......

8k15009

OK. Thanks Haner. I will try the dielectric grease. Where is the pulse module located on your truck. I have not had a chance to look for it.

Haner

Mine is on the driver's side just to the left of the power brake vacuum, when looking at it from the front. It is a rectangular box around five or six inches long. It will have an electrical connector on the left end. Remove that connector. You should see the contacts nestled back inside the box. Get a Q-tip and smear each one of the contacts, front and back, with the grease. Reattach the connector.

That should do it. Just make sure you have enough of the grease on each of the contacts.

Look at the photos on my first post and you'll see the contacts that look like blades, or fork tines, sticking out from the circuit board.

flh69

From your previous post I thought you actually opened the module, but you just put the dielectric grease on the plug contacts. Is that correct? I had mine unplugged and I sprayed the contacts with contact cleaner but did not put the grease on it. Even that seemed to help. I will definately put some grease on the plug contacts.

Haner

I actually did remove the pulse module from its case. The photos on my first post show it removed and what it looks like when it's free of the case. You don't have to do this, though, to apply the grease.

As far as the grease goes, that stuff has properties that really make the electrical connections work for a long time. I have a feeling your module is really trying to work, it just isn't able to make the proper connection. The grease will cure that problem.

Yes, put the grease on the blades (the male) of the pulse module. It wouldn't hurt to clean and put some grease on the female part of the connector as well.

flh69

Haner,
Well, I've put the grease on both sides of the plug and today it was raining so I got to try them out. They still acted up but not as bad as before. I'm going to smear some more grease on the plug and see what happens. With my luck, I'll probably have to replace the motor and module. If so, I'll get the one that is readily available. I've looked everywhere for the style that you & I have but can not find it, nor have I talked to anyone who knows what you & I have. I've even searched older & newer models with no luck. I'm beginning to believe what you said, that we are the only two people that have this style motor. Heck, maybe they are collector items.
Antique Roadshow, here we come

8k15009

Haner, I fixed my wiper problem - I replaced the unit with the newer one. It is a direct replacement, plugs right in.
Now if I can figure out why my washers won't work.

Haner

Hahahahaha!! Don't throw it away if you replace it. It might be worth a million dollars!

Sorry it didn't work for you the way I hoped.