I am still trying to track down what is causing my van to hiccup every now and then. I still think it may be a faulty throttle valve switch. Adam 12 is sending me one so we'll see. The one on the van is bad according to the multimeter. Bad news is that you can't get that stuff anymore. Some of the earlier Digifant motors in the Jetta's and Golf's had the same switch but...they're still old. It's definitely one of the concerns with owning a 20 year old vehicle that's not made anymore. Today I tested the air flow meter. Sometimes that wiper arm can be bad and show a drop in voltage at a certain spot in its movement but mine tested fine.