I have a 1999 ford ranger 4 cyl. I have
changed the battery and the alternator,
plus some spark plugs and plug wires.
Once started the voltmeter is fine but after
about 5 minutes it drops. This happened
initially causing truck to buck and stall. Any
Check to see if you bought the correct alternator for you truck. Also if you can get it to Advance or Autozone they can check your charging system for free and plug into your computer to see if your getting any other error codes that might help figure out whats going on. I'd start with the alternator though.
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