I went for a spin today and everything was fine, then all of a sudden, the rpm dropped real fast and sped past the needle and dropped below 0. I just sat there stunned for a minute, but it came back on spinning the wrong direction and started to work but said that at idle i was at 3k rpm which I know is wrong. After that, it went on and off maybe once or twice over the next 10 minutes. Any idea what's wrong and/or how to fix this. Thanks in advance,

-Chris

 

Sounds like a bum sensor. I am unsure about the FD, but on my domestic beater there's something called a 'speed' sensor which is tied in to the tach. When it's not working or not connected properly, the engine performs nominally but the tach needle goes haywire.

 

any idea how to fix this?