recently after a trip to dublin (about 200 miles all round) the car has started becoming sluggish and has lost pretty much all power. i think its started to miss fire as well. i had the head skimmed and a whole new gasket set put in about 1000 miles ago, new back box, new leads and sparks, new oil, fuel and air filters put in, new map sensor and iv cleaned the egr valve out and changed a lot of the pipes (breathers etc). reset the ecu and no fault codes or anythin are coming up yet it struggles to hit 60mph or rev over 4000... dont know what else to do now. anyone got any ideas?