I have a 92 F150 w/5.0, E4OD, and I was wondering about my amp gauge. I purchased it in April '08, and every since I owned it, the amp gauge has went passed NORMAL... I even took it to the local Advance Auto Parts to have it checked for charging battery or the alternator. It checked fine. But the battery also is leaking some acid, I have cleaned it and now it's game back. When I drive it at night, with the lights and air on the needle sits about right, sometimes.. And also when the truck is running and I roll the window down with the power button the needle moves. What could be wrong? Thanks, Jeff.

 

K, ammeters measure the amount of current flowing across a shunt in ampeers. Is your gauge labeled in amps? Becuase "normal" really doesnt mean much...

 

I don't think you have an ammeter, that's a voltmeter.

 

That's pretty normal. Use a handheld voltmeter to check your battery with truck off. Should be about 12v. Start truck and check again. At idle, should read about 14v. The voltmeter will fluctuate as you use electrical components on your truck. The fan, power windows, lights etc. Check to make sure you have good connections at the alternator and the battery.