ford focus - ford focus 1.8 td high revs - cbillington

my 2000 1.8td ford focus has started reving high. It doesnt do it all the time and not when its cold, it can be driven with out using the accelarator and when the clutch is dipped the revs go higher then drop back down. It had a clutch fitted 3 months ago. Im just wondering if anybody has any ideas what it could be? ive taken it into the garage and they said let it get worse. cheers.

ford focus - ford focus 1.8 td high revs - justju
Hi im new to this site but have read your message I have recently bought a 1.8 zetec in the last week have had problems with high revs when dipping in my clutch and tick over at start was poor and sluggish I have had it in to fords and 4 other garages and to be honest it wasnt worht the time not one of the machanic could tell me what was wrong with my car after researching some of these sites my husband may have found the problem tonight there is a split in the airflow hose going to replace tommorrow so will let you know if this cures the problem