I HAVE A 99 1 TON 2WD AND I HAVE A FEW PROBLEMS THAT SEEM TO HAVE HIT ALL AT THE SAME TIME. FIRST OFF, THE IDIOT LIGHTS ARE GOING CRAZY. ILL BE DRIVING NORMALLY AND THE WATER IN FUEL LIGHT AND THE CHECK ENGINE LIGHT COME ON FOR A SPLIT SECOND AND THEN GO OFF. SOMETIMES THEY COME ON AT THE SAME TIME AND SOMETIMES BY THEMSELVES. THERES REALLY NO PARTICULAR PATTERN AS TO WHEN THEY COME ON, BUT THEYRE NEVER ON FOR LONGER THAN A SECOND OR SO. THEYLL GO OFF AND ON ABOUT 4-5 TIMES OVER ABOUT 45 MINUTES OF DRIVING. I DID HAPPEN TO GLANCE DOWN AT MY VOLTS AND NOTICED IT STABLE AT AROUND 10-11. COULD THE ALT GOING OUT BE A CAUSE OF THESE PROBLEMS? SECOND, MY AC IS BEING TEMPERMENTAL. ITLL START OUT COLD AS ICE AND THEN DROP TO LUKEWARM IN ABOUT 5 MINUTES. IVE NOTICED THAT IF I GET MY RPMS UP PAST 2K, ITLL INSTANTLY GO COLD AGAIN FOR ABOUT 10 MINUTES AND THEN GO BACK TO LUKEWARM. I PUT A SET OF GAUGES ON IT AND FOUND THAT THE HIGH SIDE IS ACTUALLY LOWER THAN THE LOW SIDE. COMPRESSOR MAYBE???

 

when my alt went out it was doing the same thing. except it was just the check guage light coming on for a split sec. I would say it would be your alternator if it's only charging at 10-11 volts...i'd at least pull it and have it tested. if alt happens to be good, maybe the compressor is bad and drawing that heavy on the alternator

 

Check battery connections, conditions, and all grounds.

 

I FIGURED IT OUT. TURNS OUT THINGS TEND TO WIG OUT WHEN MY ALTERNATOR WOULDNT PUT OUT. I REPLACED IT OVER THE WEEKEND AND IT SOLVED ALL MY OTHER PROBLEMS. WEIRD...