That sounds quite bad. By the way, I don't think your engine is a mitsubishi one as that one is a direct injection engine with no VVT on it. You most probably have either the B4184S2 or the B4184S9, both of which are Volvo engines. You can check which engine you have with your VIN here:
http://www.volvoclub.org.uk/vin_40.shtml