[s-cars] engine speed sensor

[Martin Baggenstos]

I am having a bizarre issue with my 95 S6 and was hoping that someone could
give me some insight on it. For the past month I have noticed that on
occasion when the lights are on and I am hitting WOT, especially in 2nd
gear, the rpm gauge will move up as normal, then suddenly drop to 0 and
return back to where it should be. No problems with acceleration are noted.
One thing I will mention is that when I first turn on my lights (I am
running HID's) the rpm gauge will swing to 0 and then go to the number it
is suppose to be at. I think that when the ballast fires up, it does
something strange with the gauges. I am wondering if the HID's are doing
something strange when my car is under WOT and causing some kind of an
electrical issue, or could my engine speed sensor be slowly failing. I will
have to see if this is happening with my lights off.

Martin