so im driving home from va to my folks place in nj for the long weekend and im on 295 almost 4 hours into my trip when i lose all resistance in my clutch pedal. i was about to downshift from 5 -> 4 and it came out of gear perfectly fine but i had to literally jam it back into gear. and when i released the pedal it didnt come back as sharply as it normally does. the clutch is grabbing perfect like it always does and is not slipping one bit. the car will go into gear with no grinds or anything but i have to force it into gear but it comes out just fine. the pedal feels very spongy. im wondering if anyone has any ideas so when i bring the car to the shop tommorow i can bounce some ideas off of them rather then have em tell me its the clutch and they need my right arm and a leg. im thinking something in the hydraulics? maybe im an idiot though. any help would be fantastic.

-joe

 

this also happened to me. i was on the highway and driving about 2 hours in 5th, when i went to downshift it went straight to the floor like nothing. i pulled it back up with my foot, and repeated that about 5 more times and got all my pressure back. i have no idea what it was, but i wasn't leaking fluid and slave/master cylinders seemed fine

i bled it thoroughly when i got to my destination, been fine since.

 

Check to see if you have in Fluid in your Clutch Master Cylinder. You could have just ran out. Add and pump the clutch and see if it puts some resistance back into the pedal.
If it does, keep an eye on he Clutch Fluid level for awhile and see if you are losing fluid quickly. If you are you have a leak some where. If you can't see a leak in/around the Clutch Master Cylinder or the Slave Cylinder, you probably have a leak some where in the hard line. Which is very common for Preludes. There is a Damper in the Clutch Line and it is **** to leaking. If it's the hard line leaking, I recommend replacing the complete Hard Line with a Stainless Steal Braided line. That's what quite a few people have done on here to remove the stock hard line which has a multitude of places to leak and to remove the Damper. It's much shorter and easier to handle that the stock line and probably cheaper.
I just did this myself the past week because I was having the problem I mentioned before.
If you'd like to do this I can hook you up with everything you'll need to fix it, just let me know.