Hi i know this has been covered a few times now but just want a few ideas, iv just fitted a new engine to a astra coupe, it runs fine while idleing but as soon as its off cold stat and upto running temp it missfires when revved up and cuts out if allowed to idle, i work at a main dealers but have not really had a lot to do with these engines, the code it brings up is "p1450 throttle control malfunction", iv gone through the tis checks which say throttle body or engine ecu, iv swapped the throttle body and updated the engine ecu and its still comming back all the time. Has anyone got any ideas??? iv sprayed around for air leaks and double checked the chain timing and it all seams ok, any help would be greatly appriciated