What are the reasons for no fuel injection and no ignition?
3 Answers
There are several reasons why the engine fails to ignite: Clogged fuel injectors: Generally, clogged fuel injectors are caused by impurities in the fuel blocking the injector pathways. At certain temperatures, unstable components in gasoline can undergo chemical reactions, forming sticky gum-like substances. These substances can clog the injector's needle valves and valve orifices, affecting engine performance, reducing power output, and causing irregular engine operation. This results in intermittent ignition issues where the engine may start sometimes but fail at other times. Carbon buildup in the throttle body: Engine carbon deposits significantly impact performance by reducing engine power and causing uneven power output. They also increase fuel consumption and make cold starts difficult, leading to ignition problems and difficulty starting the vehicle. Fuel system issues: A damaged fuel pump or blocked fuel lines can result in insufficient fuel supply. Without enough fuel for combustion, the air-fuel mixture becomes too lean, making it harder for the spark plugs to ignite, which can prevent the car from starting.
Encountering issues with no fuel injection and no ignition can be really frustrating! I've faced this situation a few times, and it usually stems from problems in the vehicle's electronic control system. For example, if the Engine Control Unit (ECU) is faulty or has corrupted data, it may fail to command fuel injection and ignition. Additionally, failures in the crankshaft position sensor or camshaft position sensor can cause the ECU to receive incorrect signals, preventing the car from starting. Fuel system issues are another common culprit, such as an aging fuel pump with insufficient pressure or clogged/stuck fuel injectors blocking fuel flow. On the ignition side, burnt-out ignition coils, heavily carbon-fouled spark plugs, or a malfunctioning ignition module are frequent offenders. Don’t overlook the power supply either—a weak battery or blown fuse can paralyze the entire electrical system, rendering it inoperable. An unexpectedly locked anti-theft system can also cause this dual failure. My advice: start with simpler checks, like testing voltage and inspecting fuses. If those don’t resolve the issue, seek professional help immediately—delaying repairs can be dangerous when driving.
As a seasoned mechanic with decades of experience, I've fixed many cars that wouldn't start due to fuel injection or ignition issues. The first thing to check is the battery and fuses—if there's no power or connection, everything else is futile. Then examine the fuel pump and injectors; a faulty pump won't deliver fuel, and clogged injectors can't spray properly. If the ignition coils or spark plugs are bad, there'll be no spark. Sensor failures are common—a faulty camshaft position sensor confuses the car's brain, halting fuel injection and ignition. A malfunctioning ECU can leave the entire car unresponsive, requiring a reset or replacement. Wiring shorts or loose connections can also cripple the system. I advise against DIY tinkering—test the basics first, scan for error codes with a diagnostic tool, and get it to a repair shop promptly. Stalling on the road is terrifying.
