you need to get the car hooked upto an engine management computer, the warning light indicates a problem with any part of the management system, my car had a similar intermittent problem but it gave me a mass airflor sensor fault. i had this changed which was only £56, this stopped the fault appearing for a while.
it started missing again after 3 months and the engine light came on again. this time however after stopping and restarting it a few times it burst ino flames and is now a write off. i seriously advise taking it to your nearest vauxhall garage and getting it checked asap. the fire had started in the engine management control unit.
mikey woods
March 2008