Clutch problem, car stalls when in gear
 

NA NA miata

When the car is in neutral, everything runs perfect.
As soon as it gets in first (which requires some clutch pumping and force) it dies after a second. I can get the car moving and keep it alive if I immediately start driving.
When I tried to start it in reverse, the whole car shot backwards as I turned the key.

I thought the problem was the clutch not fully disengaging due to a leak in the slave cylinder. I took a look and sure enough after pushing down the clutch, the slave cylinder slowly loses force and after a second there is no pressure on the release fork. (But I pulled back the rubber boot, and there was no leaking under the boot of the slave)

I adjusted the clutch pedal to the point where it no longer slowly looses pressure on the release fork, but when I tried to drive the car I had the same exact problems. (But to be honest, I have never adjusted a clutch)

I have an extra slave I could replace mine with, but after trying to figure out what's wrong the slave seems like too simple of a solution.


Any insight would be helpful. If I wasn't clear or you have any questions please ask.

There is a master you know, yours is broken and leaking past the piston.

had the same problem
 

I would replaced the master cylinder too. But even after replacing the master cylinder you might have the same problem after. If so I would bench bleed the system because with the miata set up the way it is you can't gravity bleed to get the air out because the clutch line goes higher than the reservoir. Or you can buy a tool that will suck or push the fluid through. Hope this helps

+1 on the master. It will leak by and loose pressure without ant external leaks like the slave. Based on experience, if you are replacing the master, you might as well replace the slave at the same time.