hummer h2 suspension troubles

[dicko h2 uk]

hi guys, i recently bought a 03 hummer h2, here in the uk. i went out to it this morning and its now like driving a hot rod. one of the rear air bags is jacked fully and wont level itself off. ive hit the height control, thats just flashing now. ive played with the internal compresor switch, it works but doesnt do anything to help the problem.

seperate to the above, i got an engine managment light on, i pluged it in and its says a leak on the vapour system??

any ideas are welcome, you think taking your hummer to the dealer is expensive in america,,,,,,,,, try that in th uk ????????????????????

cheers