SheDrivesIt

Hot and high altitude??? I think you were down on power due to heat and lack of air. Duo have a standard Honda air box and filter?

zeroptzero

I just meant if the OP's engine was seized it would not turnover, let alone approach redline, so not likely the same situation as yours.

mmckernan599gto

Update #2:

Thinking the issue had solved itself, I decided to go on a cruise this morning into the mountains. First 20-30 minutes, car feels just fine. Afterwards, the issue I originally described began to reappear. Except this time, it seemed to be much more pronounced. Decided to cut my drive short and head home... a bit more slowly. On the way home I was able to replicate it a few times. Third gear, WOT, engine is revving out with minimal resistance and the car is not accelerating at all. At this point, I'm almost certain it's the clutch slipping. Feels like what it would if i had shifted and continued to hold the clutch in partially while trying to accelerate. At this point, after replicating it once or twice i was able to smell juuuust a bit of clutch. Nothing crazy, but it was definitely clutch (burnt out the clutch on my very first car that i learned on 7 years ago so that smell still haunts me in my sleep). Anyways, got a friend to take this video for me to show y'all how bad it was:

• Shift from 2nd to 3rd @0:05, WOT, foot completely off the clutch. Car revs all the way to redline while in third gear while the car doesn't accelerate beyond 50
• @0:14 and 0:23, 3rd gear WOT again, but it seems to catch and accelerate fine
• @0:28 downshifting from 4th to 3rd and going WOT immediately, does it again. Revs nearly out to redline without accelerating. Then it seems like the clutch grabs and the revs drop to match

At this point, I'm certain it's the clutch slipping and I just need to bite the bullet and get a new clutch cause mine is toast. I've only had the car for ~1000 miles, so it seemed possible that one of the previous owners wore out the clutch quite a bit during their ownership. Anyways, I start researching the issue with a bit of a better description than i had previously, and sure enough I come across this reddit thread: https://www.reddit.com/r/S2000/comme...tm_name=iossmf

Luckily, this post perfectly describes the issue I'm having, with a comment to corroborate. And low and behold, it seems to be an issue with the clutch rod (part of the clutch master cylinder that i replaced just the other day). In short, in my attempt to eliminate the slop in the clutch pedal after replacing the master cylinder, I seem to have tightened the rod too much to the point where even when my foot was completely off the the clutch, it was still applying pressure to the master cylinder piston. So apparently, when the car and the fluids warm up after a bit of driving, the heat build up at high RPMs and expanding fluids can cause the piston to move and the clutch to disengage partially, even when your foot is not on the clutch pedal.

Solution? Loosen the piston a tad and allow a small amount of play in the clutch pedal. Did that today and sure enough, the clutch felt just like it did before i did the CMC replacement, with a lower engagement point. Plus, when actually driving, you don't really notice the play at all since the engagement point is nowhere near the play at the top of the pedal.

Took it for another test drive, and this time i followed the same exact route i did when the problem came back just to be sure. Car performed as normal. No slipping of the clutch after numerous attempts to replicate it at the same point in the drive as before. After figuring this out, I was able to find quite a few threads on here with people who describe or warn against the same issue with an overly tight CMC rod, so I guess I'll consider myself another victim. Once again, for now, I'll consider it solved.

TL;DR: Overly tightened clutch master cylinder piston, causing the clutch to disengage partially and slip under certain conditions.

windhund116

I agree, it's the clutch. Either a miss-adjustment of the linkage or clutch disc is worn out.

rpg51

Makes sense to me. Glad you have it sorted out.
DIY guys has an excellent video up re clutch pedal freeplay. We should take care not to over due it when eliminating free play.
.

mmckernan599gto

Ironically, that's the exact video i used when trying to fix the freeplay issue in the first place... guess i should've paid attention a bit more when he said you should "leave the freeplay in the clutch master cylinder alone"

Amazing how such a small adjustment can cause such a seemingly major malfunction. Oh well, live and learn, now i know

SheDrivesIt

Confusing part was that in the original post you stated that the car would not rev to red line. Later you said that it would rev to to red line with minimal resistance without accelerating. Two very different issues. Glad you got it sorted out.

engifineer

Have fun rebuilding an F20/F22 with that damage. You cant. You trash them and find a used motor.Once the cylinders are damaged in this car the motor is pretty much junk unless it gets a full resleeve (in which case it will not be the same, will not have FRM liners, etc). and that costs as much as buying a used motor. Cant just bore it out and build like a lot of cars due to our cylinder construction If the oil level was low enough to seize the engine you can bet the cylinders are trashed.

mmckernan599gto

So yes, the issue that i described later (what was shown in the video) was definitely different to what I had originally described. The very first time i noticed something was up, it was when i was accelerating in third gear and the car seemed to hit a wall (both in terms of physical acceleration and the revs ceasing to climb), but this only happened once or twice until i noticed the issue getting worse and begin to replicate what is shown in the video on later test drives. The only explanation i can think of is that when i first noticed the problem (i.e. just before i first posted), the clutch was maybe juuust teetering on the edge of slipping/catching at really high RPMs, and it only began to really slip after I had let the heat build up after a longer drive.

I'm hesitant to say that the issue i first described is completely unrelated, as that would be quite the coincidence timing-wise. It doesn't seem to be happening anymore, but i'll definitely be keeping an eye out to see if it happens again.

engifineer

If the clutch were slipping, you would still see RPM climbing but the car would not be accelerating. I am still skeptical that this is what your issue is but just keep an eye on it when driving. And afterwards you would smell clutch burning.

Edit: Misread some of your posts so it looks like you did see engine speed increase but not vehicle speed. So that could have been clutch.