putter

into 1st or reverse. Worse with AC on. Local Mazda tech says not clutch related but rather caused by digital controls and lack of throttle cable. Says he doubts anything can be done besides raising the revs to smooth it out.

OverLOAD

Are you using Octane 93 Gas? Just try regular 87 octane for the heck of it and see what it does. It's made my RX-8 run much smoother, and it seems like there's no difference in power.

OverLOAD

B-Nez

Also, rotaries do require a bit more throttle for a smooth engagement. Give it a small blip just before engaging the clutch. If the problem persists, then it is something else...

wakeech

hey putter, welcome. which car is yours (colour/ licence plate #)?? i mighta seen it.

anyways, this is a fairly inspecific problem. just after ignition?? you've had your clutch assembly checked (or at least your VIN number) for the dreaded loose bolt problem??

if it's on normal start up (coming away from a stop, warmed up), then it probably has more to do with your driving techniques.

...the tech was simply making somehting up to tell you that he hoped you wouldn't understand well enough to refute. there is no reason that an all-electronically controlled throttle body is somehow less smooth than one actuated by a cable.

putter

Sorry, Wakeech, you probably won't see me in your fair city. I should have put Vancouver USA or Portland area in my listing.

The condition persists whether the car is cold or warmed up and has not changed in 2000mi. of driving. I sent an e-mail to Mazda and got a reply suggesting that all RX-8s have a little vibration when shifted, but I have briefly driven two other new RX-8s and both shifted much more smoothly than mine.

I drove a 5-speed Alfa Romeo (front engine rear transmission) for 13 years with no gearbox or clutch difficulties.

Please provide info on how I can check my VIN number for the loose bolt problem. Thanks.

wakeech

...crap i'm still looking for someone to gimme a ride...

Fraaaaank???

blizz81

I do NOT own an RX-8, so this issue shouldn't scare anybody But since the hydraulic clutch system is pretty similar, I figured it could apply as general knowledge...excuse me if otherwise.

So Monday before last, I get in my car and go to start it...and notice the clutch pedal lacking resistance almost all the way down to the floor. I start it and notice that I have some trouble getting it into gear (some gears worse than others). So I pop the hood and notice the master cylinder is bone dry.

In the interest of time during the middle of the week, I took it to a transmission shop and explained to them my findings, and asked them to check around for a leak and get back to me. Turns out they couldn't find a leak (the guy's speculations were amusing - just short of "the fluid seems to have vanished into a parallel fluid-limbo universe"), and filled up my master cylinder. I asked him somewhat indirectly if they bled the system and he dodged the question, so that was a "no". Hey, it was all free of charge I suppose, but I was expecting more from a tranny shop esp since I had my uncle who knows the owner give him a call beforehand. The guy also said "If you still have problems, looks like we might have to replace that clutch." Where's the rolleyes emoticon when you need it?

Anyway, my question is in regard to the curious way my car is now behaving. It goes through a cycle where, if I let it sit, the clutch pedal will eventually come back to almost normal (release point a tad high). But after 10 minutes of driving, the pedal will become increasingly stiff, and the release point continues raising, until it's at the very top of the pedal travel, and the pedal becomes stiff enough to kick my knee into the steering wheel if I'm not paying close attention. It did this from the moment I left the shop.

My hypothesis was that since they did not bleed the system, air is still in the lines. However, doing a bit of reading, it seems in pretty much all the cases I've seen where air gets into the system, the release point on the pedal gets lower, and the pedal less responsive, until the pedal is stuck on the floor and needs to be manually lifted. So my questions are 1) what exactly do you think is going on in my case, as in why are my symptoms reversed from the norm, 2) can you think of any possible harm I may be doing in driving it like this (other than maybe excessive slipping, which is bad enough) and 3) what course of action should I take?

I'm planning on monitoring the fluid level to determine if there is indeed a leak, and then find it, replace the hose/etc, and bleed the system with new fluid. That's the course of action for most that have run into the somewhat-opposite symptoms I described above, so I'm not sure if there's other suggestions that I should heed given my differences in symptoms. Thanks for any help.

Zoom2X

It sounds like a piece of dirt is blocking the inlet hole on the inside of the slave cylinder. The dirt acts like a check valve. When you step on the clutch you blow it off the hole but when you release it gets sucked back and stops the fluid from returning to the master cylinder. The clutch pedal returns to the top of it's stop and draws more fluid from the resivor so the next time you step on the the clutch it releases higher up since it didn't retract all the way last time. When you let it sit, the fluid slowy returns to the master cylinder because the dirt valve leaks a bit. I've seen this type of thing happen with brakes, to the point where the brake will not release.

blizz81

That's a very interesting take. I'd have to monitor the master cyl level over time to see if it slowly came back up, or if it dropped and went dry again.

But sounds like a bleed would address that if it was the case, and I could easily search for leaks before bleeding just to make sure none of the hoses are damaged.

I'll pay attention once I get a chance to tinker around. Would be left feeling like "this only happens to me" if that ends up to be it
Thanks much for the suggestion!

dcfc3s

If you're losing clutch fluid, it's going SOMEWHERE. Check the rubber flex line to the slave for wetness as well as the slave, but I bet you a nickel it's the master cylinder. They can leak out of the back of the assembly on the firewall side, and basically drip out inside the firewall.

With the mileage on the car, I would say you're due for a new master cylinder. They're typically not expensive and not hard to replace. Get a new one, bleed the system with fresh fluid, and I bet you'll be good to go.

Dale

blizz81

Thanks Dale - I'll take a look.

I know a couple other 4th gen maximas have seen the hose from master to slave leak over time, that seems to be the common cause from similar problems that I've been able to weed out of the maxima board.

pgtr

I agree w/ Dale, if you are not seeing moisture elsewhere like the hose/fittings/slave - look at the M/C - typically under the dash you can see a rubber boot for the push rod - peel it back & look under it - and you may find what you don't want to find - fluid. Also if the carpeting butts up against the MC on the inside - peal it back and look right up against the metal firewall/footwell...

Bleeding is very easy to do - if you havne't already - it needs it I bet. Any DOT 3 or 4 fluid will do just fine and like brake fluid - it needs to be changed periodically.

The one problem w/ driving the way it is - is that you may find yourself stranded due to lack of hydraulics to disengage the clutch with.

Slipping should not be related - that's just a sign of an old clutch that has lost too much material off the disc. To test for slipping - drop it in say 5th at about 50 or so and floor it and see if the engine just lugs along or the RPMS zing up (thus slipping).

I can't speak for the specific transmission shop you took it too of course (and hey they didn't even charge you!) but they are sometimes a mis-nomer - Trasnmission shops are really 'automatic transmission' shops for the most part. You can also take it to any independent shop or one that specializes in either the nationality of the the car or the specific make of the car over a transmission shop. Transmission shops that actually work on manual transmissions are as rare as hens teeth. But then clutch related work is about as common and standard a job as there is so anybody doing general automotive service can handle it.

blizz81

The only thing that's keeping me from buying completely into your typical master cylinder leak, or hose leak, is that my symptoms are the reverse of all the instantiations of such cases I've read/heard about.

People with such a leak seem to report a drop in their release point, eventually ending with such a lack of pressure due to air in the system that the pedal is flat on the floor and needs to be manually raised.

This I can at least somewhat mechanically comprehend. My symptoms of the release point raising to the top of pedal travel after I find the master cylinder empty, and the shop refills it, I cannot really - but I have not carefully studied how a hydraulic clutch does auto-adjustment.

The reason I cited excessive slipping was because it's harder to catch at the release point just right if it's changing on you during the drive, and it's tough when the clutch pedal is so horribly stiff and the release point is literally at the top inch of pedal travel. And actually last night I noticed when it's stiff, etc, if I give ample throttle with the clutch 'disengaged', it slips. This makes me think it's not fully disengaging when its in this state, because up to the day I noticed the reservoir dry, my clutch still grabbed fine with no slipping (not that I have done a high-gear low-rpm slip test that recently, but some hard acceleration in general).


But I will be able to look at the MC, hoses, and everything when I get in there, hopefully this weekend if schoolwork, work, etc. comply. I gave the MC a once-over on the day I initially had trouble and noticed it was dry, and also checked on the driver's side footwell and surrounding area.

blizz81

An update for informational purposes: after bleeding the hydraulics, pedal behavior has returned more or less back to normal. I think I may need to bleed from the lower bleeder to get all air out - twice I bled from the upper until air bubbles disappeared, drove around the block, then came home and bled out another air bubble.

However I still have not located the leak - doesn't seem to be at the master cyl. Only real sweat I saw was below the upper bleeder valve, and some fluid came off when I felt the bleeder nozzle, but since the valve was pretty darn tight I'm not really worried about that.

No dirt that I saw as zoom2X suggested - just air it seems. One of these days I'll remove all the crap to get to the lower bleeder and hopefully find the leak on the way to the slave cyl. Just wanted to update in case anyone ever used this as a reference in the future

S3/P3/E2

Blizz,

I had the EXACT same thing happen on my '96 3000GT. My master cylinder seals had worn out, dumping all of my fluid in the process. I had it replaced along with the fluid; however, the service shop had failed to bleed the system. Same exact symptoms - high release point, slipping, etc. Took it in and had it bled, and PRESTO - clutch back to normal like it had come from the factory.

djmano

ever since i got my 8 i have noticed that its clutch pedal feel is alot softer than probably any other car i have driven. this is great as i have very good control over clutch inputs now, and its very easy on my left leg.

however, i tried driving my friends rsx-type s yesterday, and was thoroughly embarassed when after a couple of clutch depressions my left leg was already spent!

i love the soft clutch pedal feel, even though the miata has a similar trans, all the ones i have driven have not had a clutch feel like this. am i the only one like this, or are pretty much all rx-8's like mine?

starnes

Mine is pretty soft as well, it is not very soft like my last Honda or anything but I have definitely seen stiffer. If it doesn't slip I wouldn't consider it to be a problem.

djmano

i didnt mean to make it seem like it was a problem. i really like it. i was referring only to the feel, not the holding power of the clutch. the holding power feels pretty good, i can chirp 2nd fairly easily.

nt5k

Going from the WRX to the RX8 was pretty smooth, both had light easy to activate clutches with good feedback. I don't think I would want to deal with a BMW/Infiniti clutch in rush hour traffice..

DoobyWho

I just got back from picking up some dinner and omg.. let me tell you.. im not in a good mood now.. first thing i noticed was i was sittin in line at the drive through and my shifter felt stiff, with the clutch in , i couldnt freely move it around like normal. i finally got it in 1st and started going. driving i found it hard to shift into certain gears and 3rd was almost always impossible to get into, it was griding to much.. i could drive in 4th but it sounded weird. the only thing ive done to my car was an intake. any idea what could be going wrong before i take it to mazda? should i attempt to drive it? or just have it towed to mazda? should warranty cover it?

brothervoodoo

Dooby,

I've read about the bolts on the pressure plate backing out of the clutch. Thus having problems getting into gear. I also found this thread, either way, take it in, it's under warranty.

https://www.rx8club.com/rx-8-discussion-3/bizarre-shifting-problem-11859/#post136299

DoobyWho

as of today, i drove it this morning and i still cant get into 3rd without major griding. so im just driving it and skipping 3rd, im taking it into mazda at 7am tomorrow. im leaving my intake in.

RussellP

let us know if they hassle you about the intake

Speed Racer

Sounds like your clutch and pressure plate are trashed. Same thing happened to me at 7,500 miles and Mazda did replace the clutch, pressure plate, and throw out bearing under warranty but they warned that they would only cover it once.

Digisan

Only cover it once? If someone in the service department said that to me he would hear this"$#@!$#@!$#@!$#@!$#@!". Sounds like BS to me, granted the clutch wears, but after 7,500 miles it shouldn't need replacement, hell it shouldn't after 80,000!