Gas gaudge goes up and down - 1995 Dodge Caravan

Obviously an electrical issue. You'll need to isolate what's off and on when this happens to trace the wiring for the non-working components with a 12V test light. I would suspect that if other items are still working such as the headlights, you should check your ignition switch (electrical) to make sure it's not having issues. Other than that, your ground wiring must be good for the Pos+ wiring to work properly so I would inspect that as well. Good luck:)

try doing a hard reset!disconnect the positive and negative terminals from the batterytouch the 2 ends together, and hold them there for about 10 seconds. if that doesnt work, put the key to the on position, and then start the procedure again.

check for a blown fuse in the fuse panel and if its not that pull the gauge cluster out of the dash and check the power and ground going to it cause most of the time its a bad ground wire or power wire cause people tend to kick wires under the dash on accident or they get worn or come apart

it sounds like your idle speed sensor it has to be scanned to find out for sure

Unfortunately your fuel sending unit ground, power supply or the sending unit has failed.
The circuit is open some where. There is the possibility the gauge could be bad, but check the wiring circuit first. A volt/ohm meter will do the trick when you check the circuits at the tank.
Good luck.

good question but you will have to do some testing first,, get ahold of a fuel pressuer test gaudge and test the key on fuel pressure it should be around 55lbs but each car veries so make sure to check with a repair manual to see what the exanct psi should be. once you test that then lets go from there.. put more comments up once you find out a little more and we can trouble shoot it together

sending unit is going bad...

It seems like it may not have compression, where as all you need to do to test it is get an engine compression tester, which is a gaudge with a long extension on it to check your cyllender compression. remove all 4 spark plugs, have someone crank the engine over as you hold the gaudge in place. (it may make a pop noise ot a quick hiss if you don't hold down on the tester enough and sometimes when you release it) and if you have the new parts, and the plug is getting the spark, then it may be a head or heade gaskit issue. If you don't have a compression tester, you can usualy rent them at any advance auto parts or autozone. All you do is pay for the tool upfront, and when you return it you get all your money back.
Hope this helps!

check for grounding problems for the computer area

have all the fuses been checked. if so remove the radio and see what happens