TPIGroove

I hate to beg for help, but I'm at the end of my rope. I recently acquired a 1988 'Vette that had been garaged most of its life. I'm in the process of restoring it, but one issue I absolutely cannot solve are the wipers. The wipers only activate at the top setting on the switch, and then they barely move, raising up about an inch before going back down repeatedly. I replaced the transmission, motor, motor cover/board, and nothing is physically blocking any mechanical components. I have no idea what could be causing this. I don't know for sure if the switch would cause this or not, and I'd like to know for sure before I burn more money on these things.

Has anyone ever experienced this issue before?

alexm1994

That's all that's left, replace the switch.

hcbph

About the only other thing you could try prior to doing the switch is lift the hood and see if it now works or not. Not likely but it's possible something is hanging up somewhere you're not seeing.

gerardvg

The wiper motor cover has a plastic part that needs to be fitted correctly, am at work not near my shop manual hopefully someone will post how to correctly align that plastic part in the cover.

Yes the wiper switch can go crazy with uneven sideways pressure on the ****.

If no one has posted the wiper motor diagnostic info will do it tonight.

xrav22

You may have to clean the connectors on the switch and spray cleaner inside. My wipers worked like that but after a few cleans of the switch and socket they now are working perfect for a year now. Im talking sandpapering and putting some dielectric grease.

TPIGroove

If you can get that up, I would greatly appreciate it. That may be it.

I'll try cleaning the connections when my new switch comes in.

TPIGroove

So my new switch came in... and it's not compatible. Despite being marketed to 87-89 models, when I removed my door panel the ground terminal in my car was completely different from what the replacement had, and I couldn't put it in at all.

Does anyone know at all where I can find the proper type? Why has nobody ever mentioned this difference anywhere?

I attached an image of the terminals, although my phone makes potato-quality pictures. The wrong ground terminal is the big one to the right, as you can see it doesn't match the other two smaller terminals in the slightest.

xrav22

Can you take a pic of the switch ,the green wire looks like the one on my 85.

AJRSVET

Had the same problem with my '89. The wipers would only work on the highest setting. No low or intermittent speeds. I replaced the switch. The new switch I ordered was also incorrect. I had to cut the end off of the old switch and splice onto the new switch using a crimp on butt connector. It did the trick. I now have wipers with all speeds.

TPIGroove

Here's a pic of the replacement, I'm not getting open the door again for the original. However, after looking at around, I noticed that the switches marketed at 84-85 C4s have the correct connector, so I've ordered one and I'm hoping that the stock photography of them matches the item and has the right terminal. Did GM selectively use older components in newer C4s or something? I can't fathom why my 88 would have this instead of the newer.

gerardvg

Hi

That looks like the connector in my 85, you could just splice your connector to get it going if you cannot wait?

I believe it is for the light in the wiper switch from memory.

Here is some info that might help, has wiring diagram also.
Is from my 85 shop manual. The 88 should not be too much different.

TPIGroove

New switch came in and I installed it... only for the problems to persist. Only activated on highest setting, and the wipers barely moved at all. I don't ******* get it. Is there a piece missing?

xrav22

Just checking but did you sandpaper the metal contacts(if reusing) and spray electric cleaner into the plug because they are sensitive(in the door switch)then put clear dielectric grease into the plug to continue weatherizing. Once you get them running you need to run them pouring water on the windshield. There is a plug beneath the motor it would probably need a cleaning too ensuring pproper eclectric voltage mine was dirty.
Good Luck

gerardvg

Hi

You must be pulling your hair out now...

Check the connections as mentioned by xrav22.

Check the wiring connections to the delay circuit (wiper motor cover)
And wiper motor itself.

See link to Eckler's wiper motor and delay circuit

https://www.ecklers.com/corvette/cor...-106734-1.html

https://www.ecklers.com/corvette/cor...-108640-1.html

VikingTrad3r

feel ur pain. i agree with previous couple of posts. focus in on checking for massive resistance areas. sounds like voltage is being sapped and only when u give it the full theottle does it get through and when it does its not much resulting in a slow wiper.

Racecarfan17

Maybe

RobertLang

This IS happening to me, today, right now. I am interested to read the rest of this thread.

billschroeder5842

Wha????? people WORK in Australia?

Who would have thunk that?

Dt86

My car had that problem when I went and looked at it. If I remember correctly the previous owner had to replace the wiper motor cover. There is a circuit board in it that has to do with the switch. It was hard to find and cost him about $100.

TPIGroove

I made a video in the hopes that somebody might be able to figure it out.