RPM issues

Hi all, my wife and I have a '75 Midget, we bought it about two weeks ago. It has been running fine until a couple days ago. I was on my way home and the tach. and rpm's went nuts. It was running about 4000 - 4500 rpm at idle!! pulled over and shut her down. Started it a little while later and WOW!! I got a nice sized little bang and flame out the tailpipe. Any ideas?? I am figuring the carb needs to be rebuilt. Thanks

Ignition problems often show up in the tach.
The tach sensor is wired in series from the switch to the dristributor & coil.

I would check the points first.

I would say that you almost certainly have a carb problem. You could very well also have an ignition timing problem. I'd say if you just got the car, you should get a complete tune-up regardless, and that will probably resolve the problem.

I wouldn't necessarily conclude the car needs rebuilding -- a good cleaning and adjustment may be all that is in order.

Thanks alot, I tried the points...all good there. I am waiting on a Weber...could be a little longer the folks at Weber are on strike :( Thanks Again