Volkswagen is recalling vehicles in the United States fitted with its EA288 1.8TFSI and 2.0TFSI engines because the rear camshaft lobe is prone to unexpectedly shear off from the shaft. The failure causes reduced engine power and loss of vacuum pump power, cutting vacuum supply to the brake booster and eventually resulting in increased braking effort.

"A reduction in engine power and/or increased need for braking effort after vacuum reserve has been depleted while driving can increase the risk of a crash," a statement cautioned, according to UK car consumer website honestjohn.co.uk.

The campaign affects approximately 92,000 vehicles including the 2015-2016 Beetle, Beetle Convertible, Golf, Golf GTI, Golf SportWagen, Jetta and Passat. In notifying the National Highway Traffic Safety Administration, VAG stated that the root cause of the camshaft failures has not been fully understood. The company is still continuing an in-depth failure analysis and development of a repair solution, however a fix may not be ready until the end of the first quarter of 2016.

According to honestjohn.co.uk, UK Passats are not affected because all are diesel and the GTE is powered by the EA211 1.4TSI engine. But a lot of Audis, SEATs and Skodas also have the EA288 1.8 and 2.0 TFSI engines.