Periodic High Idle and Electrical Shutdown

[Satchitananda]

This is what happen: Sometimes when I start my 1991 Festiva GL the engine will rev high, headlights won't turn on, the wipers won't work, the blinkers won't work. If I turn the car off and restart, everything goes right back to normal - engine falls back to normal idle and all electrical function returns. What is happening here? Thanks.

[Satchitananda]

Could it be a relay issue?

[Team Lightning]

I'm thinking may be a ground issue. Start by checking the grounds on the motor, and chassis. Theres a couple on the motor, one I remember on the right fender at the strut tower. I'd start with those. In my wiring diagrams, I don't see anyone item other than a ground that could be causing all those issues. I could be wrong, maybe someone else has had a similar issue and will join in.

[Aaronbrook37]

I agree with Jerry. Check for any significant resistance on your ground wires and ensure they're making solid clean contact.

[Movin]

Guess I'm the lone ranger..clean the contacts in your ignition switch. If you need info there is a thread on this with pics I need to reshoot.

[TominMO]

It could just be a worn ignition switch. While the motor is running and you don't have those other functions you mentioned, try turning the key just a little bit more (not enough to engage the starter) and see if you then get those functions back.

[WmWatt]

If you suspect the ignition switch I'd spray some WD-40 or contact cleaner into the key hole before getting into taking things apart. I've dont this a couple of time when my lights and wipers wouldn't come on consistently. Works for me for 3-4 years between sprayings. Good luck.

[Satchitananda]

Thanks so much for all the suggestions! After work I'll try them out. WmWatt: What a cool trick! Thanks again everyone.

[Aaronbrook37]

If you suspect the ignition switch I'd spray some WD-40 or contact cleaner into the key hole before getting into taking things apart. I've dont this a couple of time when my lights and wipers wouldn't come on consistently. Works for me for 3-4 years between sprayings. Good luck.

I love cheap and easy fixes! This'll go on my maintenance list for sure.

[bravekozak]

Yes, Mazda likes to run everything to ground so that they can get away with one less terminal in every relay. They have ingeniously thought of interconnecting the ground wires in a spiders web for purposes of redundancy, just in case there is any corrosion at one of the open barrel ring terminals. I doesn't hurt, every quarter century, to unscrew and clean every single ground that you can see with a Dremel mini wire brush. That will be a summer project for every single one of us.