Gti mk5 noob tube where do I start?

[Domefc]

Ok lads just swapped my a3 1.8t 2001 for a mk5 gti 2005 and to be honest it's been mistreated by my mates missus but I'm here to rescue it and give it some respect !! I started with a full cambelt kit, water pump, diverter valve replacement  because it sounded like a diesel on idle.... Made no difference by the way I've been told they all sound like that ? Sounds great after 3000 rpm and pulls OK but just feel its got more to give. So I'm thinking along the lines of cold air intake an remap any help and info much appreciated ;-)

[Saintsteve]

If your engine is the AXX engine, it'll be a worn cam Chain.. known issue on the early mk5 GTi engine.

[Domefc]

I mentioned that to the garage that was doin the work but trusted them to find the problem in the mean time called my local vw dealer because of an apparent recall on the cam shaft and chain but the robot on the other end of the phone said there wasn't one regarding my REG number (didn't even ask my engine code mate ) so to be safe they changed what I said and took my £650 :-( still I know cam shaft chain needs doin as you explained...  How much am i lookin at this time do think ?? Sorry for boring everyone but these forums are the best place for information from people who can't mug you!!

[Domefc]

Should my main VW dealer replace my cam shaft chain and follower on my 2005 gti it's had three owners full service history by independent VW specialists with 87k ?