I have a 1989 Trooper and yesterday the battery, O2, oil, gas lights came on and things were running slow. It seemed like the alternator was giving it up. It ran fine and I was going to change out the alternator. After having it tested it was not charging very high (only 11.8). It was running very poorly especially when it got warm.The lights were not on consistantly and the battery terminals were very dirty. I cleaned them up and and the problem rectified itself for a very short time about a block when I was driving home. Then they came on and were blinking on and off. When they are on the heater blows very slowly or not at all like it is not getting power. Has anyone run into this before? I am really stumped if it is not the brushed in the alternator not making contact all the time. I am puzzled as to why all the lights are coming on though. You folks seem very knowlegable and I really hope you can help. I had the engine completly rebuilt including having it bored over and I have a bad bearing in the transmission and I am afraid I might have to part ways as I can't afford to spend any more money on it even though it runs awesome. Hope you can help and it is an easy fix.

 

CHECK IT WHEN ITS RUNNING FINE (THE ALTERNATOR) IT SHOULD HAVE OVER 14 VOLTS. THEN WHEN ITS RUNNING BAD CHECK IT AGAIN PULL TO A PARKING LOT AND HAVE A DMM WITH YOU. WITH IT RUNNING PUT THE RED CABLE TO THE + AND THE BLACK TO THE -. IF IT HAS LOW VOLTAGE UNHOOK THE BATTERY AND SEE IF THE ENGINE DYES. IF SO IT IS THE ALTERNATOR. BUT DONT JUST REPLACE THE ALTERNATOR YOU NEED TO MAKE SURE ITS NOT A CONTROL WIRE OR OUT PUT WIRE. ALSO CHECK ALL YOUR GROUNDS. GOOD LUCK.