Your car’s injectors can become clogged and not allow fuel to pass through the system resulting in a lack of power and performance.
The following article discusses some common areas where debris may get trapped, causing an injector pulse problem. Have you been noticed what causes no injector pulse? A few simple diagnostic steps will help pinpoint the exact location of this issue.
Fuel Injection History
Older cars used to supply the engine with fuel using carburetors which are mechanical devices that are used to mix air and fuel.
And because the mechanical injection systems have a low adjustment that suits the different working conditions of the engines such as various temperatures, working loads altitude, and ignition timing.
The idea of electronic fuel injection systems was developed to solve the old mechanical injection systems problems so relying on the reading of a different sensor feed into a control unit analyze.
This data and give back the exact amount of fuel needed to meet better engine performance and at the same time best fuel consumption, these modern EFI systems usually consist of some basic components such as fuel pump, fuel rail, fuel injector.
We have seen two types of fuel systems, fuel injection systems in diesel engines and petrol or octane run the engine. We have a focus on the Spark Ignition engine (SI Engine), which is run by Octane or Petrol.
What is Fuel Injector?
The injector in a basic picture is an electronically controlled valve that is supplied with pressurized fuel from the fuel pump at a certain pressure level injector can be electromagnetically opened and closed at very high speed—this speed is controlled by the electronic control unit using.
PWM (Pulse Width Modulation) technique, so when the injector gets a signal from the control unit to open an electromagnet moves a plunger allowing the pressurized fuel coming out in a picture of very fine droplets.
And this happens when the fuel passes through a very highly engineered nozzle that atomizes the fuel to make it easy to burn, the amount of the fuel determined by the amount of time the nozzle is opened (Pulse Width).
How the Fuel Injection System Works?
The fuel injection system in modern vehicles is a critical component that ensures the engine receives the correct amount of fuel for combustion. This system relies on a multitude of sensors and control modules to operate effectively.
At its core, the fuel injectors are electronic valves controlled by the Engine Control Unit (ECU), which regulates the pulse width of the injector signals based on various inputs, including engine load, temperature, and speed.
When the engine is cranked, the ECU determines the appropriate injector pulse width, which is the duration the injector remains open. This pulse width is crucial for maintaining the right air-fuel mixture essential for optimal engine performance.
The ECU utilizes input from several components, including the camshaft position sensor, to synchronize fuel delivery with the engine’s operation.
Types of EFI Systems
There are three major types of EFI systems in modern automobiles. We will discuss them briefly to help you recognize the lack of an injector pulse in any of them. Single Point Injection (SPI) system has a single injector on your throttle body.
This system was disadvantageous because all the cylinders had to rely on a single injector for refueling, thus causing improper fuel distribution.
The single refueling port was based on the older carburetor model, which also faced poor distribution and uneven shape challenges.
In contrast, the multiple Point Injection (MPI) system has separate injectors near each cylinder’s intake valve. It relies on the electronic control unit for the exact fuel-air ratio for the cylinder under unique circumstances.
Gasoline Direction Injection (GDI) is the most modern and prevalent EFI. Its injectors are located at each cylinder next to the spark plug to guarantee quick fuel injection into the chamber. This system secures the highest engine performance and causes the least emissions.
What causes no injector pulse?
Since the car is trying to pump a small amount of fuel into the cylinder, the lack of an injector in the car will cause the flame to stop. “Injector pulse” problems can be caused by the following:
#1. Faulty pump.
When the pulse injector and injector are not sent due to a fuel pump failure, the car cannot start. This can be caused by a closed fuel filter or a leaky fuel line.
#2. Injector does not work.
When the injector falls off, it will stop working completely, preventing the injector pulses from being sent to the engine. Often, the car will try to start but it will not start because there is not enough fuel in the engine.
#3. Failure of the ignition cable.
Inside the ignition coil, there is a switch that can raise the current to the required level to turn on the ignition switch. When this transformer is broken, the car loses power and cannot start because the ECM does not send pulse injector to injectors.
#4. ECM failure.
If after completing all the above procedures, the car could not start and could not, the failure of the ECM may have caused the car to have any injector pulse problems.
Troubleshooting No Fuel Injector Pulse
#1. Visual Inspection.
- Check for any obvious signs of damage to the injector wiring or connectors.
- Inspect the injector nozzle for any blockages or damage.
#2. Electrical Tests.
- Use a multimeter to test the voltage at the injector connector.
- Check for continuity in the injector circuit using an ohmmeter.
- Test the injector driver using a scan tool or diagnostic equipment.
#3. Mechanical Tests.
- Remove the injector and inspect it for clogs or damage.
- Clean or replace the injector as necessary.
#4. Sensor Diagnostics.
- Use a scan tool or diagnostic equipment to check the signals from the CKP and CMP sensors.
- Replace any faulty sensors.
#5. ECM Diagnosis.
- Check for any software updates or patches for the ECM.
- If necessary, replace the ECM.
FAQs.
Q: What controls the fuel injector pulse?
The engine control unit is the electronic brain that is used to control the fuel injector pulse by gathering data from various sensors along the fuel line.
Q: What causes no power to fuel injectors?
The problem may be a blown injector circuit fuse or a fault in the wiring harness to the injector, or a bad fuel injector power relay.
Q: How do I know if my injectors are pulsing?
By using a simple diagnostic tool called NOID light, this tool detects a digital signal coming from the ECU and flashes an LED light, so if there is no LED flashing during cranking, this means that there are no pulses coming out of the ECU.
Q: How do you test a fuel injector?
By using an ohmmeter to measure the resistance between the injector’s terminals and compare it with the rated value of a good injector, usually when the solenoids shorten internally, causes a drop in resistance causes pulling much more current, which leads to a blown driver circuit.
Final Words
In general, fuel injectors may cause your engine many problems, and with a little care can last the life of the engine, and like any other part of your car, it needs to be maintained regularly.
So if you plan on running your car for a high mileages and prevent the sudden stuck, you have to regularly inspect and clean your fuel injector from carbon build ups on them.
Also, a great way to keep your injector always in a good state is by using fuel additives this will give your injector cleanliness and increase engine performance.