The truck has a new battery and alternator and both were test a few days ago to be sure their good. The voltage gauge sits in the middle of the battery picture sometimes, which seems normal. Other times it sits just below the corner of the battery on the low side. If i turn the headlights on it temporarily plummets then raises back up. Sometimes the truck will die and it will barely turn over like the battery is dead and when it starts up the gauge reads real low for a minute or two. The problem is much more common at night with accessories on like the lights, radio etc. The belt appears in great shape, I wouldnt think its slipping anyway no belt noises. The terminals are clean as a whistle and tight has can be. The battery is a new optima.... Im really unsure where to go with this problem any ideas?

 

Hmmm this is getting interesting. I just went outside and crawled around the starter area to check the cable connections and seen coolant is running down the backside of the starter. I found my mystery leak (kinda). I cant tell where in the world its coming from though and dont see any coolant hoses on the backside of the motor. I bet its wetting down the cable connections and breifly shorting out but where would it be leaking from?

 

Your right, no heater hoses, the coolant leak might be coming from a freeze plug.

 

Hard to tell about the coolant leak Shawn, we don't even know which motor your truck has.

Sounds like a bad alternator to me. Put a voltmeter on the battery terminals while it's running. Vary the engine speeds, lights, etc. (an amplified aftermarket stereo installed?)

At no time should that voltage be below 13.8-14 volts. If it drops below 14v = bad alternator.

 

I looked at his profile and it says he has a 97. I wonder if his battery cables are corroded and not getting a good connection.

 

Sorry guys i have the 4.0 ohv motor. The battery terminals are clean as can be and tight. The truck did this the day after i installed the new alternator and was doing it before i installed it as well. The old alternator tested faulty and the new one has tested fine. I checked it with a voltometer as well the charging system is working fine, its a very intermittent problem. What about an alternator relay of some sort? Battery is definitely holding a charge. I was really leaning toward the wet starter causing a short.

 

I asked my dad about the problem and he said no way is it related to the wet starter. He seems to think its the ignition and removing any extra keys on the key ring should help. He mentioned its a common problem with fords?