Riddle me this, riddle me that. Turn on my wipers, engine goes flat.

[CorsePerVita]

I have this interesting electrical gremlin I cannot figure out. Figured I'd try posting in the event someone else has had it happen either on an early 944 or 924.

Car is a '79 924, although I know the same wiper motors are used in the early 944 cars, as well as ignition switch. So I figured I'd see maybe I'll get lucky and someone has an idea. Sometimes, but not always, upon turning the wipers on or off on my car the car will die. The interesting part is that the only thing that happens is the engine shuts off. The gauges, radio, headlights, it all works fine. In fact, those stay on and don't flicker. The engine just cuts out. I can turn it off and back on and it starts right up immediately with no issues.

I'm incredibly baffled by this.

The list of things I've done:

- Rebuilt the wiper motor, resoldered connections and regreased the gear
- Fixed the linkage which was binding

After doing that the issue seemed to "happen less"

Although it started up again today
- Looked for loose connections. Cannot find any odd loose connections.
- Ignition switch has been replaced (I know, someone was going to recommend that yeah? Well, it's brand new, still continues to do it).
- Cleaned connections off for the ground from the engine to the firewall in case there is a loose ground.

The grounds all look to be in fantastic shape. I have been looking over the electrical diagram this morning and this afternoon and I cannot think of anything obvious here that would cause this.

It literally feels like someone just turns the car off. It doesn't slowly die, it just turns off, cuts off flat. Catch is... all the lights on the dash and the radio, it all stays on. Makes no sense. Cannot pinpoint it.

Anyone come across this? Have any suggestions?

Another interesting thing is that I cannot reproduce it. It isn't consistent. I even tried quickly moving the switch up and down and up and down and to no avail, it would not do it. Other times all I have to do is leave the wipers on a few seconds and blammo, the engine turns off. Today I was turning them off and it died. Turned key off and on, started back up and I kept going. Would love to figure this out though as it concerns me.

[fiat22turbo]

I think your flux capacitor needs to be charged up..... try connecting it to the town clock tower during the next lightning storm

Honestly though, I have no idea except that perhaps a floating ground is causing a problem when the motor draws too much current and seeks a new path to ground and that's through some component in the ignition system. Or perhaps you have an issue internal to your relay board that you can't see? I know I've seen them corroded and burned from the inside before.

Good luck with the search!

[mikepellegrini]

I would think its gotta be a wiring fault in the steering column.

When the car dies, does the turn signal light operate correctly? And does both left and right kill it, or is it just one direction?

The idea of a floating ground isn't bad, although I wouldn't have thought a turn signal could draw enough to cancel out the ignition. To rule that out, you might run a new ground from the battery to the cam tower, just as a precaution.

[tamathumper]

Is the steering wheel turned in a particular direction when it happens?