Hello, I'm a noob to posting but I've used the advice already present on this site plenty of times.
I've searched and not found any answers to this problem. I recently was having trouble with a code 9 and 11 on my 94 Accord LX non vtec manual tranny. Traced it back to a bad computer- two of the capacitors had leaked and corroded their legs so they were only attached to the circuit board with one leg. I swapped the computer with a used one that was from the exact same car which fixed my hard starting, missing, bucking, everything related to the codes which are no longer present. My new problem that never happened before the computer swap is that the Fuel gauge does not read full anymore. It will go to 7/8 when before it would go to all the way up as it should. My upper radiator hose got a pinhole in it the other day and started leaking and the car tried to overheat. I didn't notice at first because it was night and the temp light never came on. Turns out the temp gauge was also not going all the way up to hot, it was stopping in approximately the same place as the fuel gauge which kept the light from turning on. (so far it appears I noticed before blowing the head or gasket luckily).
Anyway, has anyone heard of a problem like this and whether it is fixable or is just another computer problem I need to just deal with?
Thanks.

 

Those two gauges are not controlled by the ECU. Those circuits are connected directly to the gauge cluster from the sensors. Could be that you have a short/loose connector somewhere under the dash after pulling the ECU out and tugging on the wire harness.