CEL - Check Engine Light
The light on the dash that should ALWAYS turn on momentarily when you turn the key on as a bulb test, and there after if/when there is an issue that needs to be addressed.


TPS - Throttle Position sensor
Used to monitor the position of the throttle in an internal combustion engine. The sensor is usually located on the butterfly spindle/shaft so that it can directly monitor the position of the throttle.


ECU - Electronic Control Unit (the car's computer).
ECM - Electronic Control Module (again, the car's computer).


VSS - Vehicle Speed sensor
Measures transmission/ transaxle output or wheel speed. The ECM uses this information to modify engine functions such as ignition timing, AF ratio, transmission shift points, and to initiate diagnostic routines.

 

I am having this exact same problem with my 95 Civic ex coupe, shifts hard and at too high RPM . Can anyone give me an exact walkthrough on how to correct this?