[RandomGex]

Hey everyone! Please bare with me while I try my best to describe the issue I'm having.

I have a 2012 Fiesta S sedan with the 5 speed manual transmission. This evening it started doing something weird. I started the car as normal, and put it into reverse to back out of my driveway. The car lurched backwards suddenly, and continued trying to move even when I mashed the clutch pedal to the floor. It was like the pedal wasn't even actuating the clutch and the brakes can only do so much. The only way I could get the car out of gear was to actually turn the car off, at which point I could slide the shifter into neutral. I started the car back up, slid the shifter into first and had the same problem, nearly crashing into my gate in the process. I turn the car off again and get out, look under the hood... though it took me a moment to realize that I wasn't likely to find the problem from the top like that. Got back in the car, started it again only to have the car behave itself this time.

Fast forward to later this evening when the gremlin resurfaced on my way back home. I was stopped at a light, and when it changed I shifted and the car lurched as it tried to take off. The clutch wasn't responding again and the car wasn't to happy about being turned off while in first gear. (Trust me, last resort.) It took pumping the clutch a few times to get it to let the shifter out of first so I could start the car again. One thing I noticed as well, was that the pedal would feel hesitant to return to the up position when the car is letting the clutch do its job. You know how you drive a car for a while and get to know it and when something is not quite right but you have a hard time nailing down how to describe it? It felt almost like normal driving, but not quite. Kinda feels like the pedal is too light coming back up under my foot and certainly makes smooth acceleration from a dead stop rather difficult.

Any ideas on what I should check?
Thanks!

 

[cventrice]

The Fiesta has a hydraulically actuated clutch. The first thing that you should check is the brake fluid reservoir to make sure that you are not low on brake fluid. Both the clutch and brakes share the same reservoir. The reservoir is to the right of the battery. If the fluid level is fine, the seal on the clutch master cylinder is probably bad. When you push the clutch pedal in, the plunger on the master cylinder is supposed to force brake fluid into the slave cylinder, which pushes on the throwout bearing, which pushes on the fingers of the pressure plate, releasing the friction disc. This disengages the crankshaft from the input shaft of the transmission. If the seal on the clutch master cylinder is bad, it cannot create enough pressure to release the friction disc. If the fluid level is low, there are a couple of possibilities. One is the you have a leak at one of the brake cylinders or calipers. This will eventually cause the fluid level to be so low that you start introducing air into the line connecting the clutch master cylinder to the slave cylinder. The other possibility is that the seal on the slave cylinder is bad. This will cause brake fluid to leak from the slave cylinder. If the fluid level is low, you will need to put the car on jack stands or a lift to find the leak. At this point, you definitely do not want to drive the car until you find the source of your problem.

 

[RandomGex]

Thanks! The brake fluid was actually the one thing I did check when I opened the hood and the level looked fine. So, it's likely to be the clutch cylinder then. I'll check it out!

 

[Scooby214]

My 2000 F150 would do this occasionally. I think it was the slave cylinder seal getting weak, but I traded it in for my '17 Fiesta before doing the slave cylinder. I was able to keep it going by occasionally bleeding the clutch line from the master cylinder to the slave cylinder. It would always have some air to purge, in spite of my staying on top of the fluid level. Once I bled the thing, the clutch would work normally for a while. Replacing the master cylinder didn't have an impact. If I had kept the truck, I would've replaced the slave cylinder (and probably the entire clutch while I was in there since it was 18 years old. As it was, I kept the thing going for a couple of years with only having to bleed the clutch once every six months.