about 3 weeks ago my speedometer went from 60 to over 120 mph and bounce back to 60. next day never did work correctly. Replace with used from wrecking yard and worked for about 1 week then did the same thing? I noticed that 1 one the pins was burnt on the old sensor, there is no damage to the wire harness or to plug. 4.0 5 speed, 120,000. all fluids changed in last 4 weeks. by the way, before this started i was getting close to 20 mile to the gal. 310 to the tank before lite comes on 16 gal tank....I travel 65 miles one way to work, with 1 size bigger than stock. I dont exceed 70 at 2200 rpm. anyway any help? [img]/ubbthreads/images/graemlins/confused.gif[/img]

There SHOULD be only very slight current flow at the sensor pins - not nearly enough to burn one. Could you have a loose ground strap at the engine that's sending the starter current try through the speedometer system? Or a loose body ground strap that's sending all of the light and accessory current through the speedo to the engine to ground?

I don't know anything about electronic speedo problems, but that's all that comes to mind.

I just had a similar problem with all of my gauges in my 97 a couple weeks ago. I just popped the fuses out, put them back in and reset the computer. It's been fine ever since. [img]/ubbthreads/images/graemlins/40BEER.gif[/img]

Use a multimeter to test it at the sensor and then again at the guage. The wire color should be the same at both locations if its different then try tapping a wire in at the sensor and running it to the guage. Only problem is that on a 97 jeep the wire may pass through the ecm also so you may want to look for it there too and test it at that point. However in most cars these days it does go to the speedo first then the ecu. hope that helps [img]/ubbthreads/images/graemlins/smile.gif[/img]

I forgot to add that if you cant figure out the color of the wire I may be able to get it for you at work tomorrow by downloading a tech sheet for alarm remote starts. let me know if its 4 or 6 cylinder and I'll find out for you.