Could a faulty ignition system cause your garage door to open by itself?

Dear Car Talk

Dear Car Talk | Aug 01, 1993

Dear Tom and Ray:

I have a white '79 Olds Starfire. About every third or fourth time I pull into the driveway, the electric garage door opens. Sometimes, the door opens when I'm pulling out of the driveway. There is no control for the garage door in my car. I haven't seen this happen with any other car but mine. Can you explain this ghostly phenomenon?
Ann Marie

TOM: There are three possibilities, Ann Marie. One is that something in your car is producing large amounts of radio frequency (RF) interference, and sending out the same signal as the garage door control.

RAY: The thing most likely to do that would be your secondary ignition system. So if you want to test that theory, put in a new set of high quality spark plug wires, and see if the problem goes away.

TOM: The second, and more likely, possibility is that it has nothing to do with your car. Other things in your neighborhood can cause the same kind of interference; airplanes, other people's garage door openers, remote-control electronic elbow massagers. In fact, the garage door may be opening at other times. You only SEE it when your car is in the driveway, but it may be opening and closing all day long.

RAY: Most electric garage door openers have adjustable settings for their remote frequencies. So having the frequency adjusted may eliminate the problem.

TOM: The final possibility is that it's your neighbor. He's hiding across the street behind his bushes and zapping the garage door opener in an effort to drive you bonkers and get you to move out of the neighborhood. Why? Who knows? Maybe he wants to make an offer on your house?

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