hi

I have a 1976 245 with B21F engine and a stick shift. Almost every time when I start it and drive off when it's cold out, my engine suffers what I call a "putt putt loss of power".
Here's what happens: I'm in 1st gear, and I push the gas pedal a little to ease out the clutch. Once I do that, I get random "spazzes" of power that kick in and out without warning. My tachometer is dancing, and my car is moving about 1 foot per second. After about 2 or 3 seconds, the engine finally kicks in, the engine speeds up to 3000 RPM, then I change to 2nd, and all is good.
I tried pushing the gas pedal when it starts to spaz, I even floored it one time and nothing happens.
I took the liberty of assuming it has something to do with the cold start injector, but is it something else?? Any help is great.

thanks!