I HAVE 94 GMC IT HAS THE 5.7 INIT
ITS HARD TO GET STARTED once I get it started sounds good as I rev it up its good till get to about 3 grand then it starts back fireing then dies and it takes for ever to get started again then its the same thing im puzzled 1 ok now the things ive done to it so far changed the plugs the cap and rotor icm and the pick up coil nothen helped I hooked up my scanner the codes it gave me said EST ESC AND FUEL PUMP RELAY OR CIRCUIT PROBLEM I GOT A RELAY OUT OF A TRUCK AT A JUNK YARD THAT TRUCK RAN GOOD IM ABOUT TO CHANGE THE SENDING UNIT NOW OH ALMOST FOR GOT THE ESC THATS THE ONE ON THE RIGHT SIDE OF THE THOUTLE BODY WHITH A 4 OR 5 WIRE CLIP WELL MY TRUCK NEVER HAD ONE ! THATS WHATS GOT ME PUZZLED THE MOST . PLEASE HELP