HI I am having a serious problem with my little corsa B.it has only done 76000 miles and was made in 2000.

when it starts it revs at 1300 unless I throttle it ,it judders and feesll ike the engine is going to fall out.so I throttle it and stay at 60 or 70 or on high gear throuhg the streets or it judders like hell .when idle it rave and sounds like it is hunting.I have changed the air mass sensor(used one) in the plastic pipe that connects to the airfilter and carb looking thing.I took off the egr valve cleanded it still no improvement.when it is juddering the engine mangement light comes on and been told it is running on safety mode and uses more fuel. any advice would be helpful please this girl needs her car to go to Munich in a few months.