
What are the symptoms of a broken fuel injector? What should I do if the fuel injector is broken? When the fuel injection nozzle is broken, the fuel injection nozzle may be blocked, unable to open, or unable to spray fuel into a proper mist.
In general, this can cause the engine to run unsteadily or even fail to operate. When the fuel injector has dripping and other failures, it may also cause excessive fuel consumption or black smoke from the exhaust.
Short-circuit and open-circuit faults in the fuel injector control circuit also occur from time to time. These faults can cause the injector to stop injecting fuel or continue injecting fuel, leading to difficult starting, unstable operation, or serious black smoke from the exhaust.
Key Takeaways
Black smoke, uneven cylinder work, vibration, reduced power, and weak vehicle performance can all point to a fuel injector issue. A fuel cut-off test and injector verification platform help confirm the fault.
Engine symptoms
Symptoms of Engine Injector Failure#
The inspection and maintenance of the fuel injector and its control circuit is an important part of electronically controlled engine maintenance. Symptoms of a broken fuel injector can directly cause abnormalities in the engine.
The symptoms of engine injector failure are:
- Black smoke from the exhaust pipe.
- Each cylinder works unevenly, and the engine produces an obvious vibration phenomenon.
- Engine power drops.
- The vehicle is weak.
Fault judgment
How to Judge Whether the Injector Is Malfunctioning#
In order to judge the malfunction of the engine injector, the engine can be run at idle speed, and the fuel cut-off test is performed on each cylinder in turn.
When the fuel injector of a certain cylinder stops supplying fuel, pay attention to the working condition and sound of the engine. If the exhaust gas no longer emits black smoke after the fuel is cut off and the engine speed changes, the fuel injector of that cylinder is malfunctioning.
After troubleshooting confirms the engine fuel injector fault, disassemble the fuel injector and verify it on the fuel injector verification platform.
Failure types
What to Do If the Injector Is Broken#
The failure of the fuel injector is as follows:
- The injection pressure of the injector is too low.
- The fuel injection nozzle does not atomize, or the obvious oil flows down.
- The length of the fuel injection jet at each injection hole of the fuel injection nozzle is different, and the fuel jet is uneven.
- The fuel injection nozzle drips oil.
- The needle valve of the fuel injector is stuck and burned.
Repair and prevention
Repair, Replacement, and Prevention#
After the above situation occurs to the fuel injector, the fuel injector should be disassembled and repaired. If the damage is severe, it should be replaced. After replacement, the fuel injection pressure should be adjusted to 22-0.5Pa, and the spray condition should be good without dripping oil.
The main reason for fuel injector failure is fuel and filter problems, such as the use of low-quality diesel fuel, or the filter element not being cleaned or replaced after long-term use.
It is recommended that users use fuel that meets the national standard. Clean the fuel filter regularly to prevent excessive oil impurities from clogging the fuel injector. If your car is experiencing any of these symptoms, the cause may be bad injectors.
Injector testing and cleaning
AUTOOL Fuel Injector Testing Options#
But, no matter what the symptoms are, you can choose our AUTOOL CT150 or AUTOOL CT200 to test and clean the injectors.
They both use ultrasonic cleaning, and the test results can be easily observed with two power versions available. It will be a good helper for you!
Need to Test or Clean Fuel Injectors?
Review the symptoms, confirm the fault with proper testing, and choose a suitable AUTOOL injector tester and cleaner for the job.
Need help choosing a tool?
Tell us your vehicle and the job; our team replies within 24-48 business hours.
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