Clutch Disengaging at high RPM?

Ben370

On my way home today, all of a sudden my car starting losing power around 4000 rpm. Almost like it’s in neutral but not quite since the shifter is in gear and the pedal comes all the way back up.
If I stay below that, it’s fine.
I checked the clutch fluid and it’s full and in good condition. Also checked the other fluids while I was at it and those are fine.

Can someone help me figure this out? Dragging clutch maybe? Could it be the linkage? The clutch worked just fine until today.

BGTV8

Clutch slip ....... how many miles has the car done

Ben370

86k miles. Does clutch slip normally happen so abruptly? I'd figure it'd be a gradual thing. This is my first manual btw...

It shifts fine but once I rev up to 4k it bucks and doesn't have throttle response...but back to normal once the revs drop.

Cyber370

Yep. Time for a new clutch.

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Ghostvette

Great time to upgrade to either the HDCSC or Z1's elimination kit. GL

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Jayhovah

Yup, no-brainer. The most expensive part of this process is the labor.

Might as well upgrade the clutch too, if only because I'd imagine a Z1 street clutch is probably far cheaper than OEM.

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Ghostvette

Hopefully, OP can find a shop that lets him provide the parts.

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Ben370

Yeah I ordered the Z1 clutch kit, Zspeed HD CSC, and OEM Master Cylinder. For fluids I got Motul RBF600 and Redline MT85.

Jayhovah

Sounds good! I am running the exact same setup with the addition of a Z1 lightweight flywheel.

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2013 Gun Metallic Sport - Gamma V3 Twin Turbogized
DIY Gamma V3 TT Install * Jayhovah's Gamma V3 TT Install Pic'Z and Vid'Z * DIY: Washer Reservoir for the Boosted

Ben370

So I changed the clutch, CSC, and master cylinder, refilled and bled clutch fluid...still having the original problem!
Could it possibly be the fuel pump?

Ghostvette

I'm hoping the mech did the complete job; flywheel, pilot bearing, and installed the pressure plate. Changing just the clutch disk, CSC & MC won't fix the problem, if you don't do the complete job.


My vote is back to the mechanic. The opening for the fuel pump is behind the passenger seat, the FSM has the location. I've heard of some folks having the fuel pump head break off and drop the pump to the bottom of the tank. Phunk has the fix for that. GL

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dP3NGU1N

Isn't the pump at the bottom of the tank anyway? The head of the fuel pump assembly has springs so that when you secure it, it provides constant pressure holding the rest of the assembly at the bottom of the tank. I think the most dangerous thing that might occur when the head breaks is that the assembly is free floating around the tank. Considering the fuel level sensor is also attached to that assembly, it will lead to inaccurate fuel level readings to boot.

Also, seems unlikely that it's the fuel pump if the car is running. I think the fuel pump is running at a constant cycle, more or less throttle has nothing to do with the fuel pump (someone fact check me, pretty sure that's how it work). There should be a separate mechanism that adjusts fuel input into the engine.

OPs issue still sounds like a clutch issue to me. The mechanic should warranty his work considering he did not solve the original issue. Hopefully you told him about the issue and didn't just pop by asking him to change your clutch without context. A good mechanic would have taken it for a test drive to ensure that the issue is fixed before returning your car.

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Ghostvette

Which is why I asked if 'every thing' got done. I've never had a clutch problem reappear, if the complete job was done. When I was talking with Kevin @FastIntentions and we were discussing the clutch upgrade, I was all for surfacing the flywheel & calling it good. He told me that on our cars, it is a better idea to replace rather than resurface. The cost to replace is nominal in the grand scheme of maneuver.

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Ben370

I did the pressure plate but not the bushing or flywheel because they looked fine. I did it myself. It drove well at first but the next day on a cold start, the issue reappeared. I drove it today and it's fine again. Seems to only happen on cold start.

Wilson2608

I think the fuel pump stays at a constant pressure like someone posted before. If not it should only have two settings (high/low). I don't think it's a fuel pump related problem though. If your car is not making a connection to the driveshaft it has to be the clutch or some other component related to driveshaft function. Flywheels have surface areas that can get worn as well.

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