At around 1000 RPMs my truck starts to vibrate really bad like it has a broken motor mount. The check engine light has been on for about 4,000 miles so I finnaly had it put on a computer. The computer said problems could be Plug and wires, O2 sensor, or the mixture control solenoid. I've replaced all but the Mixture control solenoid. I don't know exactly where it is at on or in the carburetor. If anyone can help tell me where in the carburetor is is and if I'm going to need to get a gasket kit.

fuel air sol is internal in carb remove carb top and it is in the bowl 2 wires come out top of carb rec checking it first though using dwell meter see this forum on failed emissions i lined it out how to check or write me i have replaced countless fuel air solenoids.