I've been a viewer of this board for a while and have been impressed with the collective knowledge available, so I thought you might be able to help me out!
I have a 66 malibu with a 283 2bbl and a glide. The engine idles at 1200+ even with the idle screw backed all the way off the cam. While checking for a vacuum leak, when I constricted the air flow into the carb, no change was observed. When I blocked the oil filler neck, the idle went way down. When I disconnect/plug the distributor vacuum the idle lowers, but not as much as blocking the oil filler neck. The carb is connected to the crank case exhaust port at the rear of the block. The only other vacuum connection is to the transmission. My temporary fix is to disconnect the crankcase vent from the carb, and plug the carb opening. What's the right way to fix this?

Thanks!

I don't even know if a '66 has a PCV valve, but if it does, that's where I'd start. Sounds like the "hose to the rear" might be where its located. I know some early CA cars has some wierd setups for this.

No, there isn't a PCV valve. I've read here where people have put one in line, but it didn't come from the factory with one.

Stock setup was a 90* brass fitting out of the rear base of carb with a PCV screwed into brass fitting-other end of PCV has a hose fitting which goes to the rear of block and to a baffled can under manifold. If you do not have a PCV in the line you have a large vacuum leak causing your high idle which is the reason that it slows down when you close off the only place that it can pull in fresh air(oil filler tube with a filtered cap on it). graemlins/thumbsup.gif

Thanks! I looked in a couple of parts books I have but they don't show a screw on type PCV so I'll explore hooking it up in line.
Thanks for the help!

Just Chevy,
I live in Gilbert. If you want I could come by and take a look at the car for you and give you a hand figuring it out. e-mail me if you would like some help. helopilot1967@yahoo.com