Rep Power: 0

In my 2002 Civic my instrument cluster has been on the fritz for a few months now. At first it just started dropping everything except for the blinkers and illumination. The tachometer, speedometer, temp gauge, and fuel gauge would go to zero and the odometer would shut off and the "Brake" indicator light would come on. I think I was able to get it to come back on by smacking the dash, but that may have just been a coincidence. The problem was intermittent, sometimes it would happen for days while at other times it would happen at least once every time I drove. Sometimes when it came back on the odometer would read all 8's for a bit before coming back on with the actual reading.

I took the cluster out and cleaned all of the cable contacts as well as reheated the solder joints to the connectors (I do a lot of soldering). This didn't seem to help, but the problem seemed to show up less frequently. Lately it's not only come back, but it's changed. Sometimes the fuel gauge will read differently from when I was last in the car. Today I drove to lunch and it read 7/8 of a tank on the way there. On the way back it was just above empty. The odometer has read straight 8's for a week even thought the tachometer and speedometer seem to function fine. The temperature gauge reads dead cold about 60% of the time, which is not right here in Florida.

Since everything seems to act fine at least some of the time I'm thinking it may be a connection somewhere that needs reseated or cleaned, but I have no idea where to look. I can't find any schematics for this car online and I really don't want to spend hours in the blazing sun dismantling everything. Does anyone have any suggestions or could someone point me in the direction of where to look for the other ends of these cables?

 
Rep Power: 222

check all the ecu grounds in the engine bay and check that the alternator bolts are tight

 
Rep Power: 518

Cluster self-diagnosis check?

 
Rep Power: 0

I forgot to mention that I already did the self diagnostic and it came back clean. I'll check the alternator bolts and see if I can figure out the ecu ground thing. I'm not sure what it is, but perhaps my neighbor does.

To add to the issue, last night I went to move my car out of my friends driveway, put it in reverse for the lights and held the clutch in, eased off of the brake and the engine rev'd up well over 2k. When I eased off of the clutch it began to act normal. Pushed the clutch back in and away the motor went again, foot nowhere near the gas. I moved the car to the curb and pulled the parking brake, threw it it neutral and just let the motor idle for a minute. It was purring away around 1k.

 
Rep Power: 518

Not sure what to tell you about more things going wrong.... Pick one issue, track it down and fix it, see if it affects any other issues.
I'd say swap in a good cluster and see if that takes care of the gauges issue.