I just got a 91 rs and the rpm gauge goes all the way past 7000 rpm and stays there. it sometims goes back to 0 but when i turn the key on and start the it shoots back too 7000 and stays .any ideas?

 

Have you checked the white wire off of the coil?

 

LOL I love doing this. If the wire is good coming from the coil, which I'm 50% sure it is, check out this thread. https://www.thirdgen.org/forums/elec...highlight=Tach read it in it's entirety and that will help you to determine if just some resisitors went to heck in the cluster. Just be careful when removing the cluster. In the bottom right hand corner of the cluster behind the black plastic surrounding the gauges is a type of "Module" that can be slid out to test the leads. IIRC it's pin # 4 and 10 that the resistor goes to heck. Use the thread and it'll explain it wonderfully. For reference mine was off and I replaced mine with a 196K resistor and it seems to work within 100 RPMS.