For years I have been preaching for higher level of design reuse in the automotive industry — an industry that inexplicably insists that every bolt, bracket and belt has to be unique to each model. And from time to time, a part used in one model year does not fit other model years.pReusing parts is not only helping reduce manufacturing and dealer inventory, but can also accelerate product design, improve quality and reduce manufacturing cost.

The automotive industry is slowly coming to the realization that it needs to do a much better job in focusing on meaningful and differentiating innovation and reuse existing design whenever possible. Two OEMs that I often single out as leading the pack in designing multiple models based on a single platform that allows high level of reuse are Ford and Volkswagen. But recently I found out first hand that VW does not always follow what it preaches.

My brand new Passat had a minor pressure leak in the fuel system that was probably caused by a faulty fuel filler cap. The dealer’s service department had a Passat cap in inventory, but, as it turned out, Volkswagen engineeres decided to use different fuel caps in cars equipped with 2L engine and in models using larger engines; it did not fit my car with a 3.6L V6 engine.

I am really curious to understand why VW engineers were not able to use the same fuel filler cap on all 2012 Passats (actually, why not the same cap in all VW and Audi models?)

The solution was to commandeer a cap from one of the new cars in inventory.  The new cap seems to have solved the problem. Thanks for asking.