I have a 1989 Chevrolet s10 4x4 blazer, it has a 4.3 TBI engine and 700 r 4 tranny. A couple weeks ago I was driving and went to use the right turn signal and the gas guage started to malfunction and aint accurate. The turn signals, tail lights, works, I have no brake lights or 4 way flashers that work as well as gas guage....
need help on 1990 Chevrolet S10 Blazer
It sounds like your turn signal switch may have a problem. This may sound strange, but the flashers and brake lights go through your T/S switch. The gas gauge may be reacting to a short in the switch that is drawing a lot of power. I would first get your brake lights and flashers to work, then solve your gas gauge issue. Remember, you first noticed this when you used your T/S switch to make a right turn. This is a good clue.
I had that same problem.. Check your fuse also this year model. The wiring can be going bad.. Unscrew your back bulbs and checks wires.