Intermittent Clutch on Floor

by Brian
(North Carolina)

1995 nissan 2wd 4cyl pickup 67k miles, my mom's. Intermittently about every two to three months now, works fine then push clutch in and falls to floor. Pull back up by hand just once and works fine until the next episode. Have had it checked out many times and always "nothing wrong maam". Even had flush and fluid change. There is "absolutely" no fluid leak or air which seems to be the generic answers I'm finding online. well, that and swap everything. My nine year old son can advise folks on how to solve a fluid problem. It is an actual "to church and back" vehicle that she is getting scared to drive. I need to know if there is something else going on. Were there recalls? Is there any off the wall electrical component tied to it? Nothing appears broken on the assembly under the dash, no problems changing gears, no grinding, no starting problems, actually nothing wrong with it at all except for this (and it's not the floor mat, I checked that too). Please take the time to give me an answer that will impress my son because he will give me so much crap after we replace all those perfectly good parts. Something like "I guess I'm getting a good used slave cylinder for my birthday" or "Oh goody Santa is bringing me a second hand flywheel".
Thank you so much, Brian.



Steve Says,


You didn't mention whether the clutch still worked with this problem happened (you said that there is no grinding gears so I'm guessing that maybe that means that the clutch still works) which is an important piece to the puzzle so I'll do my best without that information. There are several things that might be causing this. The first thing I would do is check the base of the clutch pedal where the return spring is located. Be sure that the spring is in good condition and that the pin that it rides on is not too worn.


You also mention that there is no leaking. You need to keep in mind however that the master cylinder and slave cylinder can both be bad even if there is no leaking. The seals inside the cylinders can cause internal leaks that you can't see.


It sounds like the whole system has been bled and the fluid has been changed so most likely there is not air in the system (unless this was not done properly) and the fluid is probably still good.


If I were the tech working on it I would suspect the master and/or the slave cylinders, but there would be no way for me to know without experiencing the problem.


There are no electrical parts to this and I don't know of any recalls. It is not a common problem, but usually when it does occur it is a seal or leak or air problem.


Keep in mind that it is possible that it could even be an internal transmission problem, but that is very unlikely. There should be no problems driving the vehicle as is until you get it figured out. It should not cause any other problems.