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1992 Toyota Corolla: What's this mystery gadget on the firewall?

A round black cylinder located high on the passenger side firewall, clearly visible when viewing the engine compartment. About 6 inches long, maybe 3 inches in diameter, oriented horizontally, with a wiring harness connected to it with maybe 6 wires. What the heck is it?

It’s never broken so never did anything with it in all these years, but I’ve wondered for years what this gadgetis. It looks exactly like an ignition coil, and it placed high up like you would with an ignition coil to prevent water splashing on it and shorting it out.

But the Toyota shop manual for the car shows the ignition coil as part of the distributor ass’y, not as an external part.

I’m wondering if it is the “igniter”, but the shop manual says the igniter is also part of the distributor ass’y, not an external part.

If it is the igniter, what the heck does the igniter do in an electronic ignition? I’d call the spark plug the igniter, after all it is the spark plug that ignites the fuel/air mixture. Is what they call the " igniter" the same thing as the points in a conventional ignition system, powering the low voltage circuit of the ignition coil?

Anybody know what that thing is?

A picture is worth 1,000 words (sometimes more, sometimes less).

Are you sure it’s not the windshield wiper motor? Your description sounds an awful lot like a windshield wiper motor. If you are not sure, turn on the wipers and feel it to see if it’s doing something.

I do agree that a picture is needed to make an accurate assessment.

Thanks for the comments. I’ll try what you said, turn on the windshield and feel it for a vibration, @mark9207. I don’t think it is the windshield motor, but I suppose it could be.

Photos? Anyone willing to provide a tutorial on how to post photos? There used to be a internet site that would allow you to upload a jpeg to it, then would provide a link you could post to a forum site like this so other’s could view it. But I’ve forgotten the name of that site, and it’s been so long I doubt it still exists. Any simple ways to do this? I can take a digital photo, that’s no problem.

To post a photo, use the “Attach a file” link below (right under the text box).

Oh, that is even more simple. Will do.

Are there any hoses or vacuum hoses attached to it?

That does look like a wiper motor. You usually don’t look under the hood and leave the wipers going after all. I’m going to google 92 Corolla windshield wiper motor. You can too. Googled it, got nothing.

This is the wiper motor

and it doesn’t seem to fit the description.

It is indeed the windshield wiper motor. I just looked under the hood of my 91 Corolla and verified it. I believe they are the same generation AE92.

@mark9207, @casper, yes, you are exactly right, it is the windshield wiper motor! Oh Oh, I admit I feel a little foolish! I always looked at it sitting there for no apparent purpose, wondered the heck what it was, and thought it was some part of the ignition or fuel injection system … lol

But I did what mark9207 said, popped the hood and turned on the wipers, and sure enough I could feel it moving in sync w the wipers. It looks exactly like the photo posted by @Rod Knox, but when it is affixed to the firewall, the most visible part is the black horizontally oriented cylinder.

I never have really thought about how the windshield wipers work. but if you think about it, it has to be sort of complicated affair, what with the various speeds, and them going back and forth instead of around in a circle. And a lot of the complicated parts that do this look like they are very difficult to access.

What I learned from all this? I hope I never have to fix the windshield wipers!

Naw, you might be surprised at just how simple it really is! Here’s a good animation and description: