Diagnosis: Customers’ complaint was the vehicle was hesitating and hard to start, then it stopped completely and was towed in. We discovered a loose battery cable and the truck was misfiring on #6. I secured the cable, cleared the codes, then test drove. The misfire came back on #6 after 4 miles. Then the plugs, wires and coil on #6 were replaced. Test drive was ok; till the next day... then the fuel pump died. So now, the fuel circuit is tested, and heavy contamination in the fuel lines was discovered.
Although cars have fuel filters designed to remove sediments from the gas, there is the possibility that the sediment gets into the engine. This causes poor performance and may harm your engine's sensitive parts. In this case it was the cause of the misfiring and the hesitation.A new pump and filter was installed, and all systems are working. In some cases, simply changing the fuel filter more often will help to reduce the amount of sediment in the tank over time. This is a common fix for the problem. The other solution is the complete removal of the tank and washing it out.