WS1

Petrol Fuel Injector Testing

Make-Toyota    Model-4A-FE

When the engine is idling, all the injectors are being actuated and opening.

i could get to all the injectors, they are in good condition.

Record battery voltage 14.23v

Cyl#1-14.91v

Cyl#2-13.92v

Cyl#3-14.23v

Cyl#4-14.82v

I checked the injectors firing when the engine idling by using an LED tester, all four injectors were flashing and working.

By using a multi-meter to get reading %(duty cycle) with engine idling.

Cyl#1-2.2%

Cyl#2-2.1%

Cyl#3-2.2%

Cyl#4-2.2%

These are the reading( duty cycle) for each cylinder by using multi-meter with shot accelerating engine.

Cyl#1-37%

Cyl#2-34%

Cyl#3-34%

Cyl#4-37%

These are the reading (Hz) for each cylinder by using multi-meter with the engine idling.

Cyl#1-47.4Hz

Cyl#2-48.6Hz

Cyl#3-47.5Hz

Cyl#4-47.2Hz

These are the reading(Hz) for each cylinder by using multi-meter with increase the engine RPM.

Cyl#1-112.48Hz

Cyl#2-112.67Hz

Cyl#3-116.65Hz

Cyl#4-116.45Hz

Calculations

At idle=Pulse width ms=(% Duty cycle X100)/Frequency

                                 Cyl#1&3 =(2.2X100)/47.4=4.64ms

                                 Cyl#2&4= (2.1X100)/47.2=4.44ms

At revved= Pulse width ms=(%Duty cycleX100)/Frequency

                                 Cyl#1&3  =(37X100)/112.48=32.80ms

                                  Cyl#2&4 =(34X100)/116.45=29.19ms

Conclusion

 This is an acceptable way to test injectors because we can measure the timing of injectors and working or not.