timing chain is a main must do job on prince engines lost count the amount i have done, if your in south west give us a call number is in my signature, think main stealers are £900-£1300 depending on whats replaced ie vanos sprockets or not and which engine makes a difference, also there are some very cheap chain kits around and they are just that febi bilsteen is genuine fitment and most expensive, FAI do a ok kit.,,
if your car is misfiring hence cleaner chances are its a chain issue as so many are, my rule of thumb on them on a car that driven mid range of revs most of time around the 60.000 miles do a part chain kit then again at 120,000 and do a full kit vanos as well. think we could do a chain kit supply and fit £700ish if all else is good in there, just call john say mike said off here etc,
as for cleaner i use cataclean in fuel tank, can use seafoam another good one will make exhaust a little whispy white smoke on idle while its in there but will clear when fuel runs out, can also use seafoam on engine oil 30 miles before oil change and will clean al carbon out of crankcase and pistons rings etc, seen this stuff turn a badly oil burning prince engine in to a using a normal amounts over a few days of running when its dirt that has caused it,
Sorry just didn't want to confuse the original poster.
