Weird ass problem

[svanhook5@comcast.net]

here is a weird problem,
I was driving home from brad woodworth's house
 last night and my car over heated AGAIN!! I let the car cool
 down and then put the key in the ignition. All of a sudden
 my instrument panel went crazy. All of the gagues would
go all the way to the top and come back down over and over
 again. I pulled out the key put it back in and then the
instrument panel started buzzing at me over and over again.
 each tone the same length and distance apart from each other.
I desided to leave the car on the side of the road overnight.
    This morning I came back put the key in again
 and it did the same thing. I then pulled the key out, put it
back in and it did not do it a gain. So I decided to try and
start it. It took a few atempts but it eventually started. Now my
 tachometer no longer works. Everything else does though.
 The car sounds and runs fine. If any one has any ideas I
would greatly apreciate it.
Thanks,
Shane Van Hook