Mitsubishi Repair: 97 mitsubishi eclipse, clutch disc, mitsubishi eclipse

Question
My 97 2.0 liter will not go into gear when engine is runnig,but goes thru gears good when off. I've checked slaves and have good pedal, I notice a drain plug on bottom of transmission and a possible fill / check plug a third of the way up but when I pulled the plug it appeared to be 2 1/2" long bolt, looks small (3/8") to be a fill plug. Am I on the right track here (possible low fluid)?

Answer
Russell: You could try to add some fluid there but you have to know if your transmission is low on fluid then you have a leak someplace. That transmission builds up on pressure, the clutch controls the pressure by useing the fluid. So when the engine is not running every thing is fine no pressure. My manual says these are things  to check if you can not change gears... faulty transaxle, faulty clutch disc, faulty pressure plate(this is the one I think is causing your problems) or pressure  plate-to-flywheel bolts loose. Working on a transmission should be left to a shop as it could be a lot of different things causing your problems. Other wise go out and buy a repair manual at any parts store for around $20.00. It will help you work through these things. But if you are low on fluid then it is leaking someplace and that must be fixed. You could have a seal out someplace too. Hope this helps and good luck!