The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post - 83 12v Cummins swap sputtering under load

NewMexCrew · 03-03-2016, 01:26 PM

HELP!! I currently have a 1990 GMC Crew Cab with an 83 12v Cummins in it. I am new to the Cummins engines. Recently the truck started sputtering under load like if it is starving for fuel. Truck starts fine and runs fine around town but while towing or going up hill at highway speeds under load it starts to sputter like its running out of fuel. If I back off the throttle it gets a little better. Any ideas on what could be wrong? Could it be the lift pump? I recently changed the fuel filter and air cleaner. Any help would be greatly appreciated.

03-03-2016, 01:26 PM	#1
NewMexCrew Registered User Join Date: Apr 2013 Location: New Mexico Posts: 44	83 12v Cummins swap sputtering under load HELP!! I currently have a 1990 GMC Crew Cab with an 83 12v Cummins in it. I am new to the Cummins engines. Recently the truck started sputtering under load like if it is starving for fuel. Truck starts fine and runs fine around town but while towing or going up hill at highway speeds under load it starts to sputter like its running out of fuel. If I back off the throttle it gets a little better. Any ideas on what could be wrong? Could it be the lift pump? I recently changed the fuel filter and air cleaner. Any help would be greatly appreciated.