I have a Holley Street Avenger carburetor that's a 660. Something is happening that seems unique. If the weather is warm it starts great with no issues. When it's cold weather it seems unique what's happening. I pump the accelerator then turn the key to start it. It starts but I have to hold the accelerator pedal down so it can run at 1600 rpms. While at 1600 it runs abit then the choke will lock in and stay stay connected until I until I kick it down with the accelerator. The puzzling point is that the choke won't set until the engine is running, but is fine after that. Any idea or opinions are appreciated.