Because turbocharged engine systems rely so much on accurate fuel delivery to perform properly, a failed fuel pump can have a drastic effect. Turbo engines require significantly more fuel flow and pressure than naturally aspirated engines, so any interruption in this flow can significantly choke performance. Based on the particulars suggested by the SAE International (Society of Automotive Engineers), turbocharged engines generally use 10 – 20% more fuel than non-turbocharged engines as combustion temperatures are high and more air on-board them; hence, the trustworthiness of the fuel pump becomes all the more obsessed.
A fuel pump is at the heart of a car’s fuel system. In a turbocharged engine you need a steady fuel pressure to avoid misfires and have proper combustion. The simplest symptom an engine will show if fuel pressure drops is hesitation, rough idling, lack of acceleration, which will be more pronounced during high-demand scenarios, meaning: full throttle or driving at speed. These symptoms are particularly prominent on vehicles with turbocharged engines, whereby the fuel pump needs to meet the engine’s elevated fuel consumption rate. According to the International Journal of Automotive Technology (IJAT), 30% of turbocharged engine performance issues may stem from poor fuel delivery.
Turboncharged engines are forced to work much harder than their naturally aspirated brethren. The additional pressure places a higher load on the fuel system, which in turn is why they require fuel pumps capable of withstanding these pressures. And a classic symptom of a malfunctioning fuel pump is a dip in fuel pressure, which can lead to lean air-fuel mixtures, or not enough fuel being supplied in relation to the volume of air being rammed into the combustion chamber by the turbocharger. A lean mixture can cause the engine to run hot, damaging the turbocharger and other important components such as the piston rings and valves.
Take high-horsepower turbocharged vehicles: If its fuel pump fails, your fuel delivery at high RPMs will be limited, just during your highest acceleration when the turbo is beginning to spool up and be demanding more fuel. This can lead to reduced power or misfire which, in turn, reduces the engine’s ability to deliver optimum performance. According to a survey of turbocharger manufacturers conducted by the Turbocharger Manufacturers Association (TMA), a turbocharged engine would encounter a 20 – 25% loss in power under conditions of insufficient fuel delivery.
Additionally, adding a turbo charger itself adds further complexity to the needs of the fuel system. Turbo engines run at high compression ratios, and once a fuel pump starts losing steam, boost pressure can become erratic due to an inconsistent fuel supply to the engine throughout a power run. As a result, the engine may suffer from delayed throttle response and hard acceleration, according to a technical bulletin by the Automotive Technology Association. Additionally, an obstructed fuel pump can cause an improper air-fuel ratio, which could lead to a greater chance of detonation or knocking, a dangerous situation in which an air-fuel mix ignites earlier than it should, and can cause serious injury to the engine.
In extreme situations, a malfunctioning fuel pump could potentially harm the engine if not diagnosed on time. The extra stress on the turbocharged components — more so if the fuel side of the system is not able to keep up — can ultimately lead to turbocharger failure or serious engine overheating. According to a Associated Society Of Mechanical Engineers (ASME) study, low fuel pressure can increase the likelihood of a turbocharger failing by as much as 40%, which contributes directly to overall engine reliability.
So it’s very important that if you own a turbocharged vehicle, the fuel pump is healthy. One way to keep your vehicle from experiencing the risks of a bad fuel pump is to perform regular maintenance like checking for fuel system clogs, checking the filter, and checking fuel pressure. A faulty fuel pump may cost between $300 and $1,200 to replace (depending on the vehicle, make and model), but that pales in comparison to the costs to replace a damaged turbocharger or even engine replacement if the turbo crosses paths with the engine before the pump fails.
However, if your turbocharged performance ride is struggling, you could be in trouble with your fuel pump. Making sure that your fuel pump is working properly can save you from having reduced power, bad acceleration and potentially damage hot engines. To learn more about high-performance fuel pumps, check out Fuel Pump.