TRUCK RUNNING SLUGGISH. DIFFICULT TO START AT TIMES. HOOKED UP TO COMPUTER A COUPLE TIMES AND SHOWED DIFFERENT SENSORS BAD AT DIFFERENT TIMES. DRIVING TO WORK ON 7/7/2005 VEHICLE SUDDENLY SHUTS DOWN, ABLE TO PULL INTO A RESTURANT PARKING LOT. PROBLEM : FUEL PRESSURE REGULATOR CLOGGED ( THIS IS A VACCUM LINE NO GAS SHOULD GO THROUGH IT) CAUSING GAS TO FLOW AT 60 POUNDS FUEL PRESSURE INTO THE INTAKE MANIFOLD CAUSING A FIRE. BECAUSE OF THIS THE MANIFOLD BURNED A BIG HOLE WHERE #4 CYLINDER WOULD BE LOCATED. THIS HAPPENED WHILE I WAS DRIVING 55 MPH DOWN THE ROAD & WAS POSSIBLY STILL BURNING WHILE I WAITED IN MY VEHILCLE TO BE PICKED UP. I BELIEVE THIS IS A DANGEROUS & SHOULD BE LOOKED AT. MY GIRLFRIENDS NEPHEW FOUND THE PROBLEM & REPLACED THE INTAKE MANIFOLD & FUEL PRESSURE REGULATOR. WHILE WORKING ON MY 99 GMC SIERRA HER BROTHER WHO DRIVES A 2000 GMC SIERRA DESCRIBES THE SAME PROBLEMS I WAS EXPERIENCING & PROMPTLY BRINGS OVER HIS TRUCK. UPON LOOKING AT HIS FUEL PRESSURE REGULATOR IT ALSO WAS FULL OF GAS ! HIS WAS FOUND EARLIER WITHOUT RESULTING IN FIRE & HIS FUEL PRESSURE REGULATOR WAS REPLACED. I CONTACTED GMC & THEY HAVE GIVEN ME A HARD TIME, BECAUSE THEY WANTED ME TO TAKE IT TO A GMC GARAGE, I WAS NOT GOING TO PAY TO HAVE IT TOWED THERE . BUT PLAN ON STOPPING THERE MONDAY 7/18/05 TO SHOW THEM THE PARTS ( I HAVE THE FUEL PRESSURE REGULATOR & THE INTAKE MANIFOLD WITH THE HOLE BURNT THROUGH)