erratic revs

[boro1986]

I have a fiesta 1.25 its been running fine but yesterday i was doing 70 on the Motorway and revs were about 3k suddenly it growled jumped to fivek and went back any ideas. TIA

[TonyBeeeee]

I suspect you may have a problem with the tacho (rev counter) or the clutch.

If it was doing 70 (at 3k rpm) and then the engine really did go to 5k your speed would immediately have leapt up to (70/3 X5) 116 mph! So maybe the engine wasn't actually doing 5k rpm but the tacho said it was.

The other alternative, which may be the growl, is your clutch started to slip, and the engine really did start doing 5k rpm but the speed didnt increase proportionately. Under these circumstances it might be wise to stay off the motorways, they are the last place you need to have your clutch pack in altogether.