Any ideas what could be causing my previously reliable used Corolla to not start every time it rains?

Dear Car Talk

Dear Car Talk | Mar 01, 1997

Dear Tom and Ray:

Help! I own a 1985 Toyota Corolla four-door sedan with a five-speed transmission. I bought it used, and it was extremely reliable for a year, then, starting at the beginning of last summer, every time it rains, the car won't start. At first, engine starter fluid corrected the problem, but not anymore. Now I need to wait for the sun to appear, and it generally takes three to four days after a rainstorm or light rain for the car to start again. I'm a poor college student, so I hope you can help me. -- Kimberly

TOM: Help you? You've got the world's most perfect car, Kimberly! Do you know how much work I could miss if my car wouldn't start for four days after every rain shower? I'd never miss a daytime rerun of "Columbo" again!

RAY: You'd best ignore him if you ever want to graduate, Kimberly. Let's start with the basics. Water, or even just moisture, can interrupt the flow of electricity from the ignition coil to the spark plugs. And if the electricity doesn't get to the spark plugs, the car won't start.

TOM: And the "classic" parts that get affected by moisture when they're old are the spark-plug wires, the distributor cap and rotor. They're all relatively cheap, so I'd start by replacing all three.

RAY: My guess is that will fix it. But if it doesn't, the problem may be in the igniter assembly, which is inside the distributor. And that requires replacing the distributor itself, which costs many hundreds of dollars. So if you need another distributor, I'd look for a used one in a junkyard.

TOM: Alternatively, Kimberly, you could just transfer to Arizona State. With all the nice, dry weather down there, you probably wouldn't miss more than two or three weeks of classes a semester.

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