Clutch pressure variation?
 

I've noticed that my clutch pedal pressure has been changing a lot recently and not in any one particular direction. Somedays, the clutch is very stiff w/a very sharp engagement point and others it's very smooth and soft with a wider engagement point. Hell, today, it went from stiff to soft to stiff all in the process of going home from the store!

How light should this thing be? I've got 3000 miles on my car and this isnt the only problem I've got at the moment. I've had 2 hard starts this week and i've had the M flash (or at least it should've been M, it might've been L).

I guess I'll take it to the dealer this weekend and get it looked at.

Any ideas?

Have dealer check pressure plate bolts!

the dealer wont want to drop the tranny just to check the pp bolts. they'll wait till it fails completely to tell you thats the problem (if it indeed is the problem)

not true. They will tear it apart if they need to. However,

They don't need to drop the tranny to check the pressure plate bolts.

with the starter removed there is access to the bolts.

I had funky clutch engagement point changes and my dealer checked and found some of the bolts to have backed out. They retorqued and used locktite.

The clutch felt wierd to the tech, and they were going to fix the problem. This incuded a new clutch assembly (which they ordered just in case they needed it).

Hmm.
Ok, so it's possible that the bolts are backing out. Would that explain the pressure changes at the pedal though?

A loose clutch cover (pressure plate) could cause a wide variety of symptoms. The pressure plate is where you get the "spring action" of the clutch. If the pressure plate moves, you will lose resistance for the period that its moving. Get that car in the dealer.

They've had my car for 4.5 hours now and they've said that they cant find anything wrong with it and I can pick it up.

I must be crazy then.

Has anybody experienced the following? During some serious cold weather the clutch pedal pressure was very high. It would improve with the engine warming up. Next day, only slightly warmer outside, the clutch pedal was very soft. Engagement point feels the same, just a very soft pedal. Any advice? I am new to manual transmissions.

This could be due to the expansion and contraction of the clutch cable in regards to temperature. I know that some people got a stainless clutch cable and that resulted in a better feel. I havent done this yet, but when I went to a stainless brake cable on my motorcycle, i found the difference to be tremendous and I got a more consistent feel regardless of the temperature.

There is no such thing as a clutch cable on an RX8!!! It is hydraulically actuated. However, EXTREMELY cold temps could possibly thicken the fluid slightly causing a stiffer feel. You may also have some moisture in the fluid causing the same problem. Outside of that I suppose it is possible the grease your throw-out bearing may have stiffened up due to the extreme cold.

Then what is the MazdaSpeed Clutch Hose that RX8garage.net sells?

Stainless hydraulic cable :D

Well it is not a cable. It is a reinforced hose that expands less under pressure making the clutch respond better when the pedal is pressed.

Same as replacing old rubber brake hose with stainless steel reinforced lines (steel braiding reinforcing rubber) to increase pressure to the brakes rather then loosing some of the pressure due to the hose expanding.

It's still hydraulic and thus a hose carrying fluid and not a cable.

gotcha

I had an inconsistant feeling clutch , felt better when cold . I had the clutch line replaced (Mazdaspeed stainless steel line) and the redline synthetic in the tranny and diff. It felt so much better both smoother and more consistant over all, I don't know why Mazda wouldn't have done it this way to begin with.

A simple and nice mod.