I took my 1989 Dodge Ram into a shop because the diesel fuel was leaking, ended up having to pay for a fuel injector pump. Now three of the four gauges on the dash do not work (fuel, oil pressure and temperature...they all read off the scale "high"). The repair shop also did work on the brake light switch, under the dash. The repair shop worked on the truck trying to find the problem for over 4 hours. They don't know what to do.

If they can't fined anything wrong with the car itself the problem might be in the sensors. IDK what kind they use in that car, but the mechanic might not have the electronic equipment to diagnose, check, or solve the problem. They may have been damaged when they fixed it, might be wear and tear, or they probably just have to be reset/ re-adjusted. Most people don't bother to fix them if that's the case cause they see it as a pointless expense if nothing is wrong with the car it's self. Another issue is replacing them. Most mechanics will opt to replace them cause it's easier and they can charge you more...then again it might be expensive for them to ship it somewhere so some one can actually fix it, and then pay them also. Most mechanics don't know much when it comes to circuitry. In ether case most people don't do anything about it and continue to use there car with all the red flags on. Ether way if it's going to brake down it will anyway and you'll still have to pay to fix it. Usually at that point people usually decide it's time for a newer car anyway and sell, donate, or junk it. If you really want to keep your car though I suggest you or some one you know to just look it over once a month and see if you can see anymore wear and terr. It's a bit obvious sometimes if there's anything physically with it. Also have a mechanic give it a thorough inspection once a year. Good Luck