I HAD IT CHECK FROM LOCAL GARAGE AND THEY TOLD ME THE

TROUBLE CODE P0400 CRITICAL SYSTEM MALFUNCTION

VICK, January 2005

ive had this problem and it is manufacturers code, i was losing power on motorways when trying overtake wich brought on the engine light and a loss of power. 1st, remove egr valve and clean it 2nd in the inlet manifold underneath the egr valve there is a row of butterfly valves , clean these thoroughly and 3rd check the vac pipes to make sure there are no holes in any of these. hope this cures it .

dave hall, April 2010

Your Garage has given you this code without telling you what the code means.Every sensor in your car has a unique code i'm not sure what sensor this is for your given code but you can find out from vauxhall main dealer

Steve Evans, January 2005