NHTSA Complaint #10894673 — 2003 MERCEDES BENZ E320

AFTER FUEL FILTER REPLACEMENT, VEHICLE OPERATED FINE FOR ABOUT 7 MILES. WHILE IDLING A COUPLE OF MINUTES IN THE DRIVEWAY UPON RETURN FROM THE SHORT TRIP, THE RETURN LINE HOSE EXITING THE FUEL FILTER EXPANDED, RUPTURED, AND SPRAYED FUEL OUT AT A HIGH RATE. AFTER HOSE WAS REPAIRED, FUEL GUSHED OUT OF EVAPORATIVE CANISTER DISCHARGE TUBE AND PURGE VALVE CANISTER. VISE GRIPS PLACED ON THE RUBBER TUBE LEADING FROM THE RETURN LINE TO THE CANISTER STOPPED THE GUSHER. NEW FUEL FILTER THAT WAS JUST INSTALLED (PRONTO PF5416) WAS SUSPECTED TO BE DEFECTIVE - CAUSING EXCESSIVE RETURN LINE FUEL VOLUME. WITH THE POOR DESIGN OF THE RETURN LINE PLUMBING AND RESTRICTION BACK TO THE TANK, THE EXCESS VOLUME WAS PILING UP IN THE EVAPORATIVE CANISTER AND OUT THE PURGE VALVE IN A MASSIVE GUSHING LEAK. ONCE A SECOND NEW FUEL FILTER WAS FITTED (PUROLATOR F65416), VEHICLE RAN PROPERLY AGAIN WITHOUT LEAKAGE - HOWEVER, SEVERE LEAKAGE FROM THE TOP OF THE EVAPORATIVE CANISTER WAS NOTED DURING A FILLUP ATTEMPT SHORTLY AFTERWARDS. THIS NEVER OCCURRED IN THE PRIOR TO THE FILTER REPLACEMENT. FROM ALL INDICATIONS, THE DESIGN IS VERY POOR AND SUSCEPTIBLE TO ANY CONDITIONS WHICH RESULT IN EXCESSIVE RETURN LINE FUEL VOLUME. THE AMOUNT OF FUEL POURING OUT OF THE TOP OF THE EVAPORATIVE CANISTER ASSEMBLY AND DISCHARGE WAS INDEED A FIRE AND ENVIRONMENTAL HAZARD - THE EQUIVALENT OF AN OPEN FUEL PUMP OUTPUT DISCHARGE. IN ADDITION TO ALL OF THIS, DURING THE FILTER REPLACEMENT/TESTING PROCESS, LOUD BANGING WAS HEARD FROM THE TANK ITSELF. REMOVAL OF THE GAS CAP RESULTED IN A MASSIVE PRESSURE RELEASE. FROM MY OBSERVATIONS AS A MECHANIC WITH OVER 25 YEARS EXPERIENCE SERVICING FOREIGN CARS, THE VENTILATION AND FUEL PRESSURIZATION SYSTEM ON THIS VEHICLE IS IMPROPERLY DESIGNED AND UNSAFE. VEHICLE WAS ON A LIFT WHILE BEING SERVICED.