92 HONDA ACCORD EX rpm hand starting to fluctuate and temp hand goes up and down
 

and engine revs up and down? ALREADY RPLACE IAC VALVE NEED HELP BAD.

Look for a vacuum leak. That is a classic sign of rough idle. After that check your wiring (especially the ground wire and battery connection). If you have a voltage meter, monitor the voltage at the battery to see if it is smooth and constant.































As for the temp hand, if the voltage is not stable that could happen also. But also after you solve the first problem, if it is still around, then check and/or replace the water temperature sensor.































Good Luck.