What is the reason for no signal power to the fuel injector?
3 Answers
The reason for no signal power to the fuel injector is that the signal line controlled by the ECU has no control signal. The ignition system should be checked for abnormalities, otherwise the ECU will not provide the fuel injection signal. The following are precautions for fuel injector use: 1. Do not reduce the fuel grade: For gasoline fuel injectors, the fuel grade represents the anti-knock performance of the fuel. Generally, the higher the quality of the fuel injector cleaner, the higher the compression ratio, and the higher the fuel grade required. This is also the focus of work for ternary cleaning shops. 2. Do not intentionally drive at low RPM: Drivers deliberately using low speed and high gear will increase the burden on the engine, and too low RPM will also cause incomplete combustion of the engine, forming carbon deposits. This is something that must be paid attention to when using fuel injector cleaners.
A few days ago, my friend's car also encountered the issue of no signal to the fuel injector, and it turned out to be a loose connector. I suggest first checking if the connector is securely attached, as vibrations can sometimes cause it to loosen. Additionally, the signal from the ECU to the fuel injector is transmitted through wiring, and if there's a break or short circuit in the line, the signal won't get through. I've also experienced cases where a blown fuse interrupted the power supply. Damage to the fuel injector itself can also cause problems, such as internal component failure. The best approach is to use a multimeter to measure the signal voltage and confirm whether the ECU is sending a signal. If all signals are normal but the fuel injector isn't working, professional tools may be needed to diagnose if the ECU is faulty. Regular maintenance can help inspect these lines and avoid the risk of breaking down midway.
When dealing with fuel injector failures, I find ECU issues to be the most common. The ECU is the core of control signals; if it's damaged or has software errors, it won't send signals to the fuel injectors. Circuit problems are also a major factor—aging, broken wires or short circuits can interrupt signal transmission, which often occurs in the high-temperature environment of the engine bay. Fuel injector failures themselves should not be overlooked, such as coil damage or internal blockages. I recommend checking the fuse box to see if the fuel injector-related fuse is blown or if the relay is malfunctioning. The simplest tool for testing signals is a multimeter—measure the voltage at the ECU output; if there's no voltage reading, it indicates a problem at the source. Never delay repairs to avoid affecting engine operation, and it's safer to seek professional help as soon as possible.
