Stricter emission tests in Germany: Many new Diesels fail to comply

The new rules in Germany, effective for almost a year, apply to diesel engine vehicles certified under the Euro 6 standard. Three years after leaving the dealership, the first technical inspection can be a big surprise for their owners. However, these are nearly new cars, not all pass the rigorous inspection.

As reported by the German automobile club ADAC, the surprising issue became well-known due to complaints from several dozen owners of Ford with a 1.5 TDCi engine and a particulate filter. Some of the vehicles failed the technical inspection due to failing the exhaust emissions test.

According to diagnosticians, the particulate filter does not fulfil its function and must be replaced with a new one. This can cost up to £2,600, a significant expense for nearly new cars. The German brand branch does not currently have approved filters but is actively working on a solution.

"The development of software updates, the delivery of improved DPF filters, and coordination with KBA are ongoing at full speed to resolve the problem," said brand representatives quoted by ADAC.

The complaints from Ford owners led the automobile club to examine the issue more closely. It turned out, the scope of the problem is much bigger and extends beyond this brand. According to data from TÜV on 950,809 vehicles inspected during technical inspections from 1 August to 31 October 2023, 32,285 vehicles did not pass the first technical inspection, which resulted in a 3.4 per cent failure rate.

The main reason for the fuss is the discrepancies between the homologation procedure and the tests conducted during the technical inspection. The homologation process considers the amount of particulate matter emitted per mile. In contrast, the German technical inspection examines the ratio of particulate matter to the volume of exhaust gases.

Representatives of TÜV and Dekra emphasize that a relatively high limit of 250,000 particles/cm³ has been set, and cars under the Euro 6 standard exceeding this limit receive a negative result in the technical inspection.

One might think that the solution to the problem would be to unify the test procedures and apply the same diagnosticians' requirements as in the vehicle homologation process. However, this is not possible due to time, costs, and technical limitations.

Following the law in Germany, vehicle manufacturers are required to meet homologation requirements, which may not coincide with the demands of diagnosticians during technical inspections.

Thus, owners of nearly new diesels that were rejected during the first inspection are in a difficult position. They have little chance of compensation from the vehicle manufacturer and rely on so-called goodwill gestures.

ADAC, therefore, appeals to manufacturers to consider the requirements of diagnosticians already at the design stage of exhaust cleaning systems so that they meet not only homologation requirements but also standards applicable during technical inspections.

The automobile club also calls for participation in the costs and goodwill gestures in cases where a nearly new car fails its first inspection due to emissions.