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Q: Truck cranks strong but sometimes will not start.

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Truck cranks strong but sometimes will not start. I have had the battery checked, the alternator and the ignition, all checked out good. I've gotten stranded with it twice so even if I go out there and it cranks up fine now, I'm afraid to drive it anywhere for fear it won't start up again. What could cause that? It has been happening for the past 2 weeks. Before then I never had a moments problem with it. Fuel pump? I hear the fuel pump come on. Can you help?

My car has 60000 miles.
My car has a manual transmission.

A: Hi, thanks for writing in. This can happen ...

Hi, thanks for writing in. This can happen for many different reasons, but based upon the fact that it sounds like you may have had to have it jumped a couple of times suggests that you may have a charging system problem. If the battery and alternator have both been tested as good, you may have a faulty voltage regulator. This is a unit that monitors the charging of the battery by the alternator. When this is not working properly, this can either overcharge or undercharge the battery in some cases and is often an intermittent problem. If you would like help, consider having an expert automotive technician from YourMechanic come to your home or office to inspect and diagnose this issue for you, and make or suggest any repairs as needed.

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