A car will often start and then stall out where the fuel pump is heat soaking and losing pressure when warm as this normally two different failure modes in a fuel pump that commonly fail once it gets hot. Fuel pumps are arranged to distribute 40-60 psi of pressure and this is steady, the engine is supposed to operate harmoniously. A decreased loss of fuel pressure might occur if the pump overheats. The former causes a fuel starvation phenomenon, which in turn causes stalls — especially under load and during long drives. In the worst cases, an overheated pump might cause internal components to swell and resist fuel flow.
Once miles pass the 100k yardstick the older pumps iberate heat as even better. And when the internal motor of the pump wears, it needs more power finishes heat. The pump heats up and eventually, this heat causes it to lose its efficiency levels by as much a 15-20% which has a cascading effect on engine performance. Additionally, this practice of running on low fuel causes the pump to burn up since it uses fuel as a coolant. When you hit near-about quarter of tank, the pump no longer remains fully submerged and overheats up fast.
Electrical problems can make this problem even worse, such as bad ground connections or broken wires. This behavior could cause the fuel delivery system to work intermittently and then stall due to an overheated fuel pump not receiving a steady 12-volt supply. Even 1-2 volts can raise the risk of stalling by exposing the pump to wide changes in output, and heavy loads when it needs to provide more fuel.
Ford recalled a number of vehicles in 2019 for stalling problems linked to fuel pumps that could overheat. The pumps in those vehicles would stop working after said 20 minutes, and drivers found themselves stranded as a result. It also emphasizes the key role of temperature management as far as optimum fuel pump performance is concerned.
The clogged fuel filter is one factor that will cause the gas pump to heat up. When that filer gets restricted it makes the pump work harder to push fuel through it and when you make your pump work harder, guess what happens—more heat gets created. It is recommended that mechanics replace the fuel filter every 30,000 miles otherwise it could block and make the pump overheat which in turn would cause a failure. Without this maintenance, a further 10–15% of the pump load is applied which may snatch one pump stop.
Tech mogul Henry Ford once said, “Failure is only the opportunity to begin again, this time more wisely. Identifying Fuel Pump Failure Symptoms In The Early Stage Also Helps Control Overheating Costs And Improve Your Car's Reliability.
For an overview on fuel pump diagnosis and other overheating information, see the Fuel Pump.