How to Adjust Excessive Fuel Injector Return Flow?
2 Answers
It may be caused by a damaged filter screen, allowing fuel containing impurities to enter the fuel pump and injector, resulting in poor fuel atomization and difficulty starting. Clean the fuel system pipelines, replace the fuel filter, repair or replace the fuel injector (test and adjust the injection pressure), and then try starting again.
As a seasoned veteran in automotive repair, I recall that excessive fuel return through the injectors is typically associated with injector malfunctions. Issues like clogged nozzles or worn needle valves can cause excess fuel to flow back into the lines, leading to increased fuel consumption and even black smoke emission. The adjustment process should follow a step-by-step approach: first, check if the fuel filter is dirty—replace it if contaminated; then test whether the injectors spray fuel evenly—if uneven, use professional cleaning agents, and replace them entirely if cleaning proves ineffective. Also inspect the fuel return line connections for looseness or leaks—tightening screws or replacing seals can resolve minor issues. Finally, examine the fuel pressure regulator—if pressure is too high, it must be replaced as these are generally non-adjustable. Having handled several such cases myself, I always advise owners against pushing DIY repairs too far and recommend prompt inspection at authorized shops to avoid fuel leaks in the engine bay, which pose a fire hazard.
