Clutch judders, especially in reverse. This means the gearbox mountings on the cross member are breaking up. Fit a new one. The steady bar rubbers may also be worn out, fit new ones. It will only cost #15. Using the WRONG oil in the gearbox will be the culprit of eating away the rubber mountings. Hypoy oil ruins rubber, causing it to swell up and go all soggy.
Clutch judders, and you can smell burnt oil. Clutch plate is contaminated with oil. Yous hould be ready for this if the oil leak out of the bellhousing is bad, and it is your fault for not curing it. This is a RARE fault, as it is quite difficult for oil to get into a spinning clutch, as it will be thrown off. Check the mounting first!
Once you have pushed in the clutch, it lets itself in. A pretty frightening fault, as you sit at the lights, foot on the clutch pedal on the floor, and the car moves off! It is the clutch master cylinder seals, they leak internally. As seal kit will cute this. This is often accompanied by a fluid leak above your feet, out of the clutch master cylinder, where is runs down under the carpet. Check the brake ones as well.
Clutch pedal spongy means air in the pipe. Probably a slave cylinder leaking as well. Of you fit a seal kit, do both ends of the system.
Clutch fluid goes down. You've got leaking from either the master of slave cylinder. You will eventually lose the clutch. The pedal will be useless. In an emergency, put water in the reservoir, BUT ONLY TO GET HOME. Flush it out ASAP. If you know you have a leak, and cannot fix it till next week, carry a tin of fluid with you, better still, fix it.
Clutch 'spins' or 'slips', (same thing.) Engine RPM rises rises as you accelerate, but car seems to not go any faster, nearly always on a hill start. New clutch is needed, the plate is worn out. You may get away with just a new plate, but often a new cover is needed as well. ALWAYS fit a new release bearing with a new clutch.
Vibrating feeling when depressing the clutch pedal, or it feels lumpy, and you hear grinding noises, and infers a worn clutch release bearing. It is chewing away the clutch cover, see above paragraph.
Clutch very heavy can possibly mean someone has fitted a diesal clutch cover with stronger springs or the slave cylinder seal is sticking. A seal kit will cure this. Another possibilty is that the insides of a flexible hose has broken up, restricting the fluid flow, restricting the fluid flow, giving a heavy feel to the clutch pedal, but this is rare.