hi everyone i know this has been covered before but i need a refresh ion this i realise they are loud in the morning from cold (172 engines) but bewteen 2-3 revs my engine is very tappety even more so when the air con is on...now i have not had the aux belt and idler tensioner replaced or the cambelt could it be the aux belt in particular that is generating this noise any help greatly appreciated cheers...the car has always been serviced and just had fully synthetic elf oil put in