Diagnostics and repair of mechanical and common rail injectors

Proynov diesel service carries out diagnostics and repair of mechanical and common rail injectors with the brands Bosch, Delphi, VDO (Siemens, Continental) and Denso.

Components subjected to diagnostics and repair at the service are:
• Single and double spring-loaded mechanical injectors BOSCH and DELPHI
• Common rail injectors CRI BOSCH for light and light weight vehicles
• Common rail injectors CRIN BOSCH for heavy duty vehicles, agricultural and construction equipment, marine vehicles
• Common rail piezo injectors BOSCH
• Common rail injectors DELPHI for light, light weight vehicles and agricultural machinery
• Common rail piezo injectors VDO (Siemens, Continental) for light and light commercial vehicles
• Common rail solenoid and piezo injectors DENSO for light and light weight commercial vehicles
• Proynov Diesel Service offers BOSCH exchange injectors

The following actions are performed during inspection and repair:

Dismantling the injectors from the vehicle

Visual inspection for mechanical damage

Cleaning of the mechanical and common rail injectors in ultrasonic cleaning equipment

Injection testing for fuel delivery and back leak quantities and a high pressure test

Determine the problem

Replace the worn components

Calibrating the injector

Generate a correction code unique to each injector and issuing a protocol from the test

Installing the injectors on the vehicle

All mechanical and common rail injectors received for inspection at Proynov Diesel Service are initially cleaned in ultrasonic cleaning equipment to remove the accumulated carbon deposits. It is only after this cleaning process, that they are mounted on a test bench where the actual diagnostics of the components are carried out. The mechanical injectors are inspected on an BOSCH EPS 100 test bench, monitoring the fuel spray, sound quality and pressure at which the nozzle starts to inject fuel. After the observed results, a specialist determines whether there is a need to change the nozzle or other part of the injector which is being inspected.
For the correct inspection and calibration of common rail injectors, different manufacturers have selected and certified specific test stands. BOSCH have developed their own stands for their injectors, and DELPHI, DENSO and VDO authorize checking and calibration on a HARTRIDGE stand. For all types of common rail injectors, the amount of fuel injected into the different modes of vehicle operation is checked as well as the amount of back leak flow. Stands are programmed with an extensive database of all current common rail injectors and are highly accurate. Each step of the test procedure is reduced to minimal deviations, ensuring optimal operation of the injector and the engine, respectively. After the completion of the entire test procedure, a test protocol and injector evaluation report is issued. In order to determine the exact problem of the injector, a thorough analysis must be carried out. It involves complete disassembly and examination of the worn parts, under a microscope if necessary. It is only after the completion of these steps that the diagnosis of the injector and sometimes of the vehicle can be correctly specified. If repair is necessary and desired by the client, the disassembled injector again goes to the ultrasonic cleaner to eliminate built up carbon deposits of poor quality fuel. The repair of the injectors can be as minimal as replacing only the valve or the nozzle or it can be significantly involved, if the circumstances require it. The spare parts used are original, certified and factory-warranted. Assembly and calibration of injectors are done through designed software and a wide range of measuring instruments required by the manufacturer. As diesel technologies become more advanced, the precision needed to repair these components is almost surgical. It is important to note that only certified Bosch and Delphi Hartridge stands can generate a new correct injector code.