Thanks Richards. I found it this morning after poking around under the hood a bit. I was going to put the multimeter on it, but the truck is running great today. I have to dial the idle back down to 'normal'. Yesterday it wouldn't idle and I had to dial it out 3 full turns. <img src="/forums/images/graemlins/scared.gif" alt="" /> I was going to just replace the sensor, but at $70 some odd dollars, I think I'll postpone until I can get a definitive answer. Damn thing is only 16 years old... <img src="/forums/images/graemlins/lol.gif" alt="" />