The operation of motorcycles with fuel injection systems has been a great boon to riders all over the world. The convenience offered by such a precise method of delivering fuel to the engine improves engine reliability, reduces emissions, increases fuel economy, and ensures more consistent power delivery. However, like any other system, fuel injection systems can also encounter problems. The Harley Davidson motorcycle is no exception to this rule and has its own set of issues that can arise from a clogged fuel line or injector, air intake filters, low-quality gasoline or low fuel pressure levels. It is important to understand the source of these problems so that you can properly diagnose and repair them in a timely fashion.

What Is Fuel Injection?

Fuel injection is a method of introducing fuel into an engine cylinder by injecting it under pressure directly into the combustion chamber rather than via a carburetor or intake manifold as in traditional gasoline engines. It allows for more precise control over the air/fuel mixture to ensure optimum performance and efficiency. Fuel injection systems use computers to precisely monitor and adjust the amount of fuel injected based on signals from various sensors that measure engine speed, load, temperature, etc., which leads to improved performance and efficiency compared with outdated carbureted engines.

Common Harley Fuel Injection Problems

Harley Davidson motorcycles are equipped with Electronic Control Modules (ECMs) which allow for better control over the motorcycle’s operation by monitoring various engine parameters such as exhaust gas recirculation (EGR) or intake air temperature (IAT). However, with this increased complexity come certain problems which may need to be addressed.

  • Dirty Air Filters: Dirty air filters can reduce the amount of air entering the engine, which reduces performance and efficiency. It is important to regularly check and replace the air filter to ensure that it is not clogged with dust or debris.

  • Clogged Fuel Lines and Injectors: Over time, fuel lines can become clogged due to debris or corrosion from water in the fuel system. This can also cause injectors to become blocked as well, resulting in poor performance and poor fuel economy. To prevent this, it is important to regularly flush out the fuel system using a good quality cleaner.

Solving Harley Davidson's Fuel Injection Problems

  • Poor Quality of Gasoline or Low Fuel Pressure: Poor quality gasoline can lead to deposits in the fuel system that eventually block up the filters and injectors, resulting in poor performance. Low fuel pressure from a malfunctioning pump can also cause similar issues as it will not be able deliver enough fuel into the engine efficiently. It is important to check both of these factors when diagnosing any potential issues with your motorcycle’s fuel injection system.

  • Faulty Sensors and Switches: If a fuel injection system is not functioning correctly, it may be caused by faulty sensors or switches. The sensors could be sending incorrect readings to the ECM, resulting in incorrect fuel delivery. It is important to check all of the sensors and switches to ensure they are functioning properly before attempting any further repairs.

  • Exhaust Leaks and Implausible Airflow Readings: Exhaust leaks can cause implausible airflow readings, which can lead to an incorrect air/fuel mixture being delivered to the engine. This can cause a variety of issues such as poor performance or stalling at idle. It is important to check for any exhaust system leaks that may be causing this problem before attempting any other repairs. If having trouble with your Harley’s ignition switch? Learn about the common issues and potential solutions in this comprehensive guide about Harley Ignition Switch Problems.


Harley Davidson motorcycles are equipped with complex fuel injection systems that can encounter a variety of issues if not properly maintained. Dirty air filters, clogged fuel lines and injectors, poor quality gasoline or low fuel pressure, faulty sensors or switches, and exhaust leaks are some of the common problems that you may encounter with your Harley’s fuel injection system. By understanding the source of these problems and taking steps to address them in a timely manner you can keep your motorcycle running smoothly for years to come.

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