1996 Chevrolet Impala Fuel System

FUEL PUMP FUSE BLOW OUT. THE CAR CUTS OFF AND STOPS WHILE DRIVING, BLOWING OUT THE FUSE. WHEN A NEW FUSE IS INSTALLED AND THE ENGINE IS STARTED, IT BLOWS OUT AGAIN. THE PROBLEM IS CAUSED BY A FAULTY WIRING HARNESS TO THE FUEL PUMP ASSEMBLY. THE WIRING ON THE FUEL PUMP SENDER UNIT MELTS AND PEELS BACK THE INSULATION, CAUSING THE BARE WIRES TO TOUCH AND SHORT AGAINST THEMSELVES OR GROUND OUT AGAINST THE CAR. THIS OCCURS RIGHT AT THE TOP OF THE FUEL PUMP TANK ON THE SENDER ASSEMBLY OR JUST INSIDE THE TANK. THE FUEL PUMP WIRING HARNESSES ON THESE VEHICLES ARE PROBLEMATIC AND DEFECTIVE, POTENTIALLY CAUSING A FIRE IN THE FUEL TANK AND EVENTUALLY A CATASTROPHIC EXPLOSION. A NEW FUEL PUMP SENDER (OEM PART NO. 25028955) WAS REPLACED IN ADDITION TO A NEW ELECTRIC FUEL PUMP, AND NEW FUEL FILTER. *JB

ON 7/2/2000 I WAS RETURNING HOME FROM A TRIP AND MY CAR WENT DEAD WHILE I WAS DRIVING ALONG AT ABOUT 35 MPH. I WAS ABOUT 5 MILES FROM HOME WHEN THIS HAPPENED SO I GOT THE CAR OFF THE ROAD AND CONTACTED MODERN CHEVROLET IN WINSTON SALEM NC ON MONDAY MORNING AND HAD THEM PICK THE CAR UP FOR REPAIR. WHEN THEY CONTACTED ME THE SAME DAY THEY TOLD ME THE FUEL PUMP FUSE HAD BLOWN OUT AND MY CAR WAS READY TO PICK UP. WHEN I PICKED THE CAR UP THEY TOLD ME IF THE FUSE BLEW OUT AGAIN THAT I MAY NEED TO HAVE THE FUEL PUMP REPLACED. THIS REPAIR COST ME $150.00. ON AUGUST THE 20TH, 2000 I WAS ON THE WAY HOME FROM A TRIP WITH MY COUSIN AND WE WERE ABOUT 150 MILES FROM HOME TRAVELING EAST ON I-40 AT ABOUT 65 MPH WHEN THE CAR WENT DEAD AGAIN. I MANAGED TO GET THE CAR OFF THE ROAD AND GET ASSISTANCE TO GET IT HOME. I LEFT IT AT MODERN CHEVROLET AGAIN FOR REPAIR. THAY CALLED ME THE NEXT DAY AND SAID THE FUEL PUMP NEEDED TO BE REPLACED SO I TOLD THEM TO GO AHEAD. AS IT WENT THE FUEL PUMP AND THE SENDING UNIT BOTH NEEDED REPLACING. I TOLD THEM I WANTED THE PARTS WHEN THEY FINISHED. WHEN IT WAS ALL OVER THIS COST ME $1050.00 IN REPAIR AND TOWING. WHEN I RECEIVED THE FUEL PUMP AND SENDING UNIT WHICH I HAD TO ASK FOR AS THEY DIDN'T LEAVE IT WITH THE VEHICLE I FOUND THE WIRING TO THE PUMP HAD SHORTED OUT SOME HOW AND THE WARE WAS BARE FOR ABOUT AN INCH AND HAD SHORTED AGAINST ANOTHER WIRE. THIS WAS AN IN TANK FUEL PUMP AND SENDING UNIT AND I FEEL I WAS LUCKY THE VEHICLE DIDN'T CATCH ON FIRE. I HAVE THE FUEL PUMP AND SENDING UNIT IF IT IS NEEDED.

GMC IN RECENT YEARS HAS REPLACED MOST OF THE FUEL LINES ON ITS VEHICLES WITH A FLEXABLE NYLON FUEL LINE. THIS WAS DONE TO SAVE MONEY AND MAKE INSTALLATION EASIER. THE METAL END FITTING ARE JUST ATTACTED TO THE LINES BY SHIRNK RAPPING THE NYLON LINE TO THE FITTINGS. AS PER GM'S OWN SERVICE MANUAL THESE NYLON FUEL LINES ARE VERY VULNERABLE TO DAMAGE FROM CHAFFING, SHARP OBJECTS, HEAT. THE SERVICE MANUAL STATES THAT THESE FUEL LINES MUST NOT BE EXPOSED TO TEMPERATURES ABOVE 190 DEGREES F. FOR MORE THAN AN HOUR, OR 235 DEGRESS AT ANY TIME. THE ENGINE COMPARTMENT ENVIRONMENT OF THIS VEHICLE CAN FAR EXCEED 235 DEGREES F. I HAVE SEEN THE LINES SOFTEN FROM EXPOSURE TO HEAT AND THE SHRINK RAP AT THE METAL END FITTINGS RELAX. THESE LINES ARE USED BEFORE THE FUEL PRESSURE REGULATOR AND ARE EXPOSED TO THE FULL FUEL PRESSURE THAT THE FUEL PUMP CAN GENERATE. THIS CAN BLOW THE ENDS RIGHT OFF THE NYLON LINES WHEN THEY ARE EXPOSED TO HEAT ABOVE 200 DEGREES F. THIS CAN CAUSE A MAJOR ENGINE COMPARTMENT FIRE SINCE THERE ARE SEVERAL IGNITION SOURCES (ELECTRICAL SPARK AND AUTO IGNITION FROM HEAT)

THE FUEL GAUGE WAS READING FULL WHEN THE VEHICLE WAS ON EMPTY DUE TO A SHORT THAT HAD WELDED WIRES TOGETHER INSIDE OF THE TANK. DEALER HAS REPAIRED VEHICLE.

I FOUND TWO VEHICLES THAT HAD THE FUEL PUMP HARNESS WITH MELTED WIRES. I THOUGHT THIS WOULD BE OF INTEREST TO THE NTSA BECAUSE OF POSSIBLE FIRE HAZARD

FUEL METER ASSEMBLY (SENDER) FAILED.