Hi there this is my first post so please be kind to me!!
I have a C reg 1.8 8v convertible golf Gli, which i have had sitting for a while now but have started to try and get it on the road.
Now to the problem, although this has sat for several months now it would always start and idle fine, but i have recently changed the spark plugs, oil, oil filter and air filter. once i had did this it wouldn't start for ages and now when it does it runs like a bag of crap for a few seconds and then dies. However, if you rev it it revs fine and also drives if you keep the revs up.
I have not got a clue what i could have done and this is starting to do my nut!!! The only thing that i have noticed now but couldn't say before is that around the area where the air filter goes there is a light hissing sound and i'm panicking that i've knocked something off?

Does anyone have any ideas??? Also is it ok just to change these parts or should i have changed other things too.
Any help with this would be greatly appreciated
Thanks
Chris