misfire on fiesta

[vimcy2000]

i have a v reg fiesta that has an unpredictable misfire...it has when the engine is cold, hot, wet or dry...i have had the ignition coil the th leads and the spark plugs change but none of these seem to work..it runss fine for a month or so after the errors have been cleard from the computer..does anyone have any odeas as to what the problem could be? :confused:

[fiestaman]

I have a similar problem with my 2000 reg fiesta. It started hesitating when accelerating and now runs lumpily. I have replaced the sp plugs and ht leads with no success. does anyone have a theory as 2 what the problem could be? The car is a 1.25 manual with 48,000 on the clock.