I have a 1995 Jeep Wrangler with about 170k miles. 2.5L 4 cylinder, 5 speed manual. A while back my speedometer started to act up. For some reason it will not read accurately all the time. Sometimes it will read perfectly, for anywhere between 5 to 105 miles it will be fine, I do 55 mph it will read 55 mph. Then all of the sudden, other times it will stop reading correctly. The speedometer needle will continue to move but it would not give the correct speed, for example I could be floored in 5th flying down the highway and it will say i'm doing 40 mph. I thought it was the speed sensor so I replaced that and the speedometer gear. I made sure it was in correctly, multiple times, but I still have the same problem. I use a drill and the speedometer works. I tore the dash apart thinking it could be something electrical, but was not able to see anything in the dash that would cause this problem. I am lost on what else could be causing this unless its something with the ECM. It is currently giving a code for O2 sensor, but I don't think they would be related. Any thoughts?