Since about two oil changes ago, I have been having some erratic oil pressure guage operation. While looking into the problem, I noticed that the there is a sensor mounted low in the block, just below the starter with a wire broken off (there is photo of the sensor on page 174 of the haynes manual). Is this the oil pressure switch? If this is the oil pressure switch, can this cause erratic guage readings? It seems to run just fine, and occasionally the guage will read correctly, but most of the time it reads low. I would think that it was the engine, but it started all at once, like something that could have been triggered by a broken wire. I did a search and found a couple of posts that mentioned the oil switch, no definitive answers about the switch affecting the gauge. I know the gauge is driven by the sender, but can the switch with a broken wire cause poor gauge readings? It seems odd that the Trooper even runs with a wire broken on the oil pressure switch <img src="/forums/images/graemlins/confused.gif" alt="" />