Over recent years, we have invested in our workshop. We now have state-of-the-art common rail test bench facilities to test modern diesel injectors of solenoid and piezo technologies.


In recent years, more and more drivers have been drawn to diesel-powered vehicles. High-pressure injection systems, unit injectors, and common rails have transformed the ponderous, smoke-belching slowcoaches of yesterday into the sporty, fuel-efficient, and clean automobiles of today. The common rail system in particular gives engine developers the freedom they need to reduce exhaust emissions even further, as well as lower engine noise. With its flexible division of injection into several pre, main, and post-injections, the particular design of common rail allows the engine and the injection system to be matched to each other in the best possible way.

In the common rail accumulator injection system, the generation of the injection pressure is separate from the injection itself. A high-pressure pump generates in an accumulator - the rail - a pressure of up to 1,600 bar (determined by the injection pressure setting in the engine control unit), independently of the engine speed and the quantity of fuel injected. The fuel is fed through rigid pipes to the injectors, which inject the correct amount of fuel in a fine spray into the combustion chambers. The electronic diesel control (EDC) controls extremely and precisely all the injection parameters required to run a modern diesel engine efficiently as possible.

In the 1st and 2nd generation of Bosch's™ common rail, the injection process is controlled by a magnetic solenoid on the injectors. The hydraulic force used to open and close the injectors is transmitted to the jet needle by a piston rod. We have now moved on to the 3rd generation of common rail for passenger cars, the injector actuators consist of several hundred thin piezo crystal wafers. Piezo crystals have the special characteristic of expanding rapidly when an electric field is applied to them. In a piezo inline injector, the actuator is built into the injector body very close to the jet needle. The movement of the piezo packet is transmitted friction-free, using no mechanical parts, to the rapidly switching jet needles. The advantages over the earlier magnetic and current conventional piezo injectors are a more precise metering of the amount of fuel injected and an improved atomization of the fuel in the cylinders. The rapid speed at which the injectors can switch makes it possible to reduce the intervals between injections and split the quantity of fuel delivered into a large number of separate injections for each combustion stroke. Diesel engines become even quieter, more fuel efficient, cleaner, and more powerful.


Here at Weymouth Mobile Mechanics Ltd, we're able to test all diesel injectors of pintle and common rail design. We can also rebuild, recondition, and supply new injectors to suit your requirements. Bosch EPS diesel testing available £20 + VAT per injector and comes with a complete detailed print out with every injector included in the price. Don't hesitate to get in touch with our team when you're in need of assistance.

Contact us today, in Weymouth, Dorset, to discover more about the work of our car mechanics.