First of all I'm not even sure where to put this so I put it here since this one gets the list views but if I'm in the wrong place please feel free to move me mods.

So I bought a rpm window switch from jegs performance part no 40824 and its acting up, the rpms on it are steady and then suddenly it shoots up 2k rpms higher. Like if I'm at 4k it'll read 6k for a second and go back down and it does that constantly, could it be my tach signal? I got my tach signal from the passenger side. I think it was a blue wire I don't remember, I tapped into it a while back when I installed my shift light, anyways is that a good tach source or where is a good one? Where would the best signal be? Also I have my shift light connected to the same wire too so could that be it? Any one ever use one of jegs rpm window switchs? I'm going to contact jeggs to see what they say but I thought is ask you guys to see if maybe it was something I did wrong or forgot to do. Here's a link to the one I got http://www.jegs.com/i/JEGS-Performan...71#moreDetails