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Q: What causes a major power loss while going down the highway?

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While driving, I lost all power, but the engine was still running. Made a pretty bad noise a few times while driving... made it home driving very slow. Kinda sounded like that clicking you hear when you have a dead battery but worse. All gauges went dead. I noticed the battery slowly losing juice then the bad clicking noise and everything shut down but the engine...

My car has 200000 miles.
My car has an automatic transmission.

A: Hi there. The problem you are describing, l...

Hi there. The problem you are describing, losing electrical power while driving, sounds like a charging system problem. The PCM (powertrain control module) has been engineered to recognize low charging voltage and systematically shuts down accessories to keep engine running. The clicking noise may have been coming from the alternator and/or serpentine belt tensioner assembly. I recommend having the charging system inspected. It may be, the only problem your vehicle has is a faulty alternator. I recommend having your vehicle diagnosed and repaired by a certified technician from YourMechanic.

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