CarTalk.com Best of Deals Car Reviews Repair Shops Cars A-Z Radio Show

Battery dies in rainy/ humid weather

I’ve got a 95 Geo Prism. It doesn’t look like the best car around, but for what it’s worth, it’s gotten us around for the last 2.5 years fairly reliably. In those 2.5 years we’ve replaced the alternator, the starter, the plugs, wires, and distributor. The distributor cap is missing a gasket, but it’s on real tight.



The current problem we are experiencing is that occasionally the car will not start. It behaves as though the battery has died, but when given a volt meter test, the battery shows full charge. Sometimes the car starts if we take the cables off the battery terminals and put them back on. There is no apparent corrosion on the cables. When given a jump, it starts, but won’t stay running. The problem seems to be worse when it is humid out, or when it has rained for an extended period of time, though it is very unpredictable when it will choose not to start. Often times I will drive some place with no problems and find that once I return to the car, it will not start.



What in the world is happening? Has anyone had this problem before? Help!

What was the voltage measurements (no load and with starter engaged) ?

There could be internal corrosion and you may need to replace the cables, or those parts that “look” OK may well be corroded and need cleaning. Of course it could also be the battery.

A trip to your local auto parts store, where they likely will check out the battery and charging system for free.