Expert: Brad Sears - 7/15/2008

Question
I have a 66 Mustang that was given to me ( I know! Awesome gift!) Anyway, I havent had any trouble starting it.  My problems arise after it is started.  If I don't give the engine any gas, the engine stalls.  I have to really rev the engine once I start it to avoid stalling it.  It has only been doing this recently, which leads me to believe it is a hot weather issue (90-100 degrees for the last few weeks.)  I admit that I run pretty low on gas usually a half to a quarter tank so I might be starving the engine for fuel, I'm not sure.  It has stalled on me sitting at lights and in traffic, but easily starts back up, again, only if I rev it real well.  Also, while at said lights and in traffic, the engine likes to surge and when going 40-50 mph or so, it feels like it sputters slightly ( I have assumed I just have good hearing and notice small changes in the sound of the engine when it's running :) ) In the spring months the car ran like a dream and almost never encountered these problems (still surged a little).  I drive her every day and rely on this car, so I am wondering if there is something that needs to be fixed, or if it is as simple as letting it cool off or pouring water on some hot parts when its scorching outside.  It is a straight 6 automatic, and thats basically all I know about it.  Any advice would be appreciated!

Answer
It sounds like it could one of several problems. One, the carburetor could have some dirt in the idle passages and need to be cleaned, that is taken apart and cleaner not cleaner in a can. The second cause could be a vacuum line leaking or disconnected. After all these parts are probably just over 40 years old and getting brittle.
Brad