Petrol Injector Servicing

Unlike Diesel injectors, the electronic Petrol injector is a sealed unit and cannot be dismantled or have any of its internal components replaced. Only the external components and the internal filter basket can be replaced. All rubber fuel and air seals should be replaced if the injectors are removed from the engine.

Our Asnu machine was specifically designed for servicing and testing electronic petrol injectors. This test equipment allows us to perform accurate testing of flow rates and spray patterns under controlled conditions. This equipment also allows us to ultrasonically clean the internal components of the injectors to remove rust, carbon and lacquer deposit from the injector, all of which can cause flow and spray pattern problems.

Some of the symptoms listed below could indicate that your injectors are faulty and not working to their full potential.

  • Starting Problems…Difficult to start, hot or cold or will not start at all.
  • Poor Fuel Economy…Vehicle has good performance, but excessive fuel consumption.
  • Excessive Exhaust Emissions…MOT failure on exhaust emissions, no adjustment available. Lambda or Catalyst exhaust failure.
  • Idling Problems…Erratic and un-even idling, surging, misfiring, ‘pinking’ and adjustment fails to resolve problem.
  • Lacking Performance…Lack of power, flat spots, poor throttle response, car not performing like it should or use to.
  • Poor Driveability…The car hesitates, ‘pinks’ under load, erratic performance and throttle response.
  • ECU Error Warning Codes…Error code shows fault with Lambda or Air/Fuel mixture and checks show no fault.

There are three main faults that can cause you to suffer from the above problems. These are indicated below along with the knock on effects that these faults can have on your vehicle.

  • Leaking Injector Valves will cause: Wetting of the manifold walls, this can cause starting problems, bore wash, lacquering of the lambda sensor and clogging or failure of the catalyst exhaust.
  • Poor Fuel Distribution & Atomisation will cause: Excessive exhaust emissions, poor fuel economy, idling problems, lack of power, poor driveability, gumming or sticking of the inlet valves, lacquering of the lambda sensor and clogging or failure of the catalyst exhaust.
  • Un-even Fuel Delivery Rates will result in: Incorrect exhaust emissions, lambda sensor and catalyst exhaust problems, idling problems, lack of power, poor driveability.

This illustration shows six injectors all with varying spray patterns and an explanation of their condition.

The Fuel Delivery and the Fuel Distribution can simultaneously be measured and visually examined.

The Distribution is measured by the length of penetration into the delivery tube.
The ideal requirement would be that all the penetrations reach the same length (see arrows and red line on picture).
An imbalance in the distribution length would cause a change in the Air/Fuel ratio.We will need your injectors to test and service. You will receive a full test results sheet with before and after figures. Contact us for the latest prices and availability.