The following measures serve to determine the cause(s). It is recommended to run all the measures and then to create the inspection report. The inspection report shows a summary of all the results and repair instructions.
Matching the eccentric shafts
The initial positions of the eccentric shafts of the Valvetronic can deviate due to tolerances. The DME matches this automatically up to a difference of 5°. Here, only one eccentric shaft is adjusted at a time. The display shows the corresponding matching angle for this side. 0° is displayed or the other side. Fluctuations of up to 0.4° are permitted. If a constant matching angle of 5° is displayed, the adjustment range of the DME is no longer sufficient and the DIS tester must be used to adjust the initial position of the eccentric shaft by 5°. This is then the new initial position for the DME
Rough operation values
Disturbances in the fuel injectors, the ignition system, unequal cylinder fill levels at minimum stroke and leaks in the combustion chamber change the rough operation values. A statistical evaluating run automatically by the test module can pinpoint the cause. This measurement has is particularly informative if the compression check does not indicate any deviations.
Compression test
The compression test can be used to detect unequal cylinder fill levels at minimum stroke and combustion chamber leaks. Combustion chamber leaks are characterized by great deviations in the measured values at minimum stroke and at maximum stroke. Unequal cylinder fill levels at minimum stroke only cause deviations in the measured values at minimum stroke. A measurement at minimum stroke must be carried out first. Using these results, a decision is made in the test module as to whether a measurement at maximum stroke is also necessary. During the compression test at minimum stroke, the matching of the Valvetronic eccentric shafts is suppressed. For this reason, the measured compression values of the two cylinder banks cannot be compared directly. A correction is made in the test module.
Check of intermediate lever wear:
The wear can be limited to individual positions on the contact face. This is why the test covers every position. Irregularities on the contact face caused by wear lead to irregular operation.