Hopefully I can help..
What engine size do you have?
Any warning lights come on since or prior to the problem?
What sort of mileage does it have / any previous service and work history?
If at all possible can you describe the sort of noise your hearing?
its 1.2 and know the person i bought it off has always run a1 no warning lights nothing was running fine day before and noise when you accelerate is like a tapping noise
Hi..there thanks for getting back..
Ok..by the sounds of your description it could well be missfire/multiple misfire and thus this can cause lack of power and juddering at idle/tapping like sound through the rev range etc..things that would need to be checked would be the spark plugs / coil,leads ensure the leads are fully seated into the plugs/coil etc..so those would need to be checked anyway..other causes could be timing issue although this should really be picked up by the ecu if the cam/crank sensors are running out of sync - but well worth having the belt check anyway.or an injector issue.they can have isues with ecus and give exactly the same syptoms but again usually the eml light will flash indicating a fault codes has been stored..But as above it would be worth checking the basics first ie: sparkplugs remove and see if any are fualty/fouled up etc/HT leads etc.I do hope this helps