1992 Plymouth Acclaim Lossing Power

It sounds like your charging system is quitting. First, be sure the belt isn't loose. If you can catch it while it's acting up, measure the voltage across the two battery terminals while the engine is running. It must be between 13.75 and 14.75 volts. If it's low, measure the two voltages on the two small terminals on the back of the alternator. One must have full battery voltage. The other one should have less, typically somewhere between 4 and 11 volts. It must not have 0 volts. If it does have 0 volts, the brushes are worn. They can be replaced, but most people just replace the entire alternator.

Those voltages must be measured with the engine running. There will be 0 volts on both wires when the engine is not running.

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