Of course, yes, a failed fuel pump can surely cause hard starts due to the failure of the fuel system to deliver continuously the amount of fuel needed for the ignition of the engine. When a worn pump and blockages are used in a fuel, it loses pressure, hence cannot be able to pump enough fuel to the engine for starting. Standard fuel systems operate in a range of 40-60 PSI, whereas a failing pump can only achieve a small fraction of that, not even near what is necessary to keep fuel properly flowing. Several automotive studies have demonstrated that for every 10% drop in fuel pressure, firing becomes considerably more difficult-especially during cold weather when the viscosity of the fuel increases.
The other major contributor to hard starting involves faults in the fuel pump relay, in that the relay is generally like a switch, controlling power to the pump. A bad relay can have the pump turning on late, leading to a delay in ignition. Relays wear out over time, and high mileage, over 100,000 miles, tends to be very prone to this kind of failure. As such, according to mechanics, hard starts happen 20% more often on older cars.
Low fuel levels are another very deceiving factor in startup performance. Because the pump relies on fuel to cool it, this will lead to an increasingly high chance of overheating and undue wear that will ultimately reduce pressure and might result in hard starts. Keeping the tank above a quarter full is not only good health for the pump but also aids in consistent fuel delivery while starting.
Faulty check valves inside the pump can also lead to hard starts because they let the fuel drain back into the tank upon the ignition's turn-off condition, which results in loss of prime. Without this prime, it takes longer for the pump to build up enough pressure to start the engine and causes delays in starting. Regular inspections involving fuel system components, particularly for those vehicles over 10 years old, will go a long way in early fault detection.
A good quality Fuel Pump investment, supported by routine maintenance, is required to keep the starts reliable and evade those pressures leading to related problems.