I just picked up my 92 RS yesterday and now I got to get it where I can drive and not have any worries for the most part. I have searched around but havent got to find a definete answer yet so any help would be appriciated

Tach - it goes up and down but isn't right. Somtimes when you start the car it shoots all the way up and sticks there and acts like some of the lower RPM's is 0... Turn it off and it can stop anywhere from 0 to maxed or anywhere in the middle.

Fuel gauge- The guy I got the car from said that when you fill it up it stays pegged out at the F mark for a while but when it gets down to 1/4 its about empty. Its says that is is at the F mark now but I know that it was drove about 50 miles and haven't moved and don't know what to make of that yet.

Hatch Release- When you hit the button for the hatch to raise itself it just unlocks it from the hook and the motor run for ever. I couldn't figuer that one out on here from the post except for the struts might be bad or its out of alligment. I finally had to unhook the battery from it so it would stop whining.

Temp Gauge- The guy I got it from says that it is a false reading cause the put a digital themomitor on it and it is running the correct temp even though the gauge says that it is overheating. He drove it to my house the day I looked at it and that was a good 50 miles and it wasn't over heating then so I don't know what that could be either

 

Regarding the hatch release, the problem may be mechanical as opposed to electrical. The hatch release unit has a plastic gear inside which turns the circular motion of the electrical motor into the up-and-down motion of of the hatch itself. Those gears, not surprisingly considering the material, tend to break over time. When you push the switch to open the hatch, the motor is turning, but the hatch won't move. Since the only thing that shuts the motor off under normal operating conditions is the latch/unlatch switch, which is triggered by the hatch reaching full up position, the motor will keep on running with the broken gear--unless, that is, you disconnect the power which is what you did. I'd suggest you take the hatch release unit apart--it's not that difficult--and check the gear. If it's stripped, you can order a new one for about $10 from Top Down Solutions, which is where I got mine when I had the same problem.

As for the fuel gauge, it could be a number of things, very few of which are easy to get to, given what a pain it is to drop the tank on one of these cars. The typical GM fuel gauge should read F when the sender shows 90 ohms, and empty at 0 ohm respectively. Consequently, any increase in the resistance path from the gauge to the sender would indicate a tank fuller than it actually is. You may be able to get to the sender wire itself somewhere and ground it, which should cause the gauge to read empty. Then, if you have disconnected the wire, you can ground it through a 90 ohm resistor, which in turn would cause the gauge to read full. At least you would know at that point whether it's a gauge problem. If the gauge reads what it should, then the problem is probably in the sender (stuck, dirty, bent arm, etc.).

I won't even hazard a guess as to the other two; hope someone on the board can point you in the right direction though. Best of luck

 

The three gauge issues could all be symptoms of a bad ground. Might want to clean connection at firewall. Under the hood next to heater/AC box. Should be a grounding strap going to engine from there as well.