I have a 1987 ramcharger with a 318 and auto tranny. I just put a new carburetor on it. The previous owner partially deleted the lean burn system but didn’t change out the carb. I put a Carter 2bbl on it. The truck will start fine and drive fine until I try to go down hill, it then stalls. It doesn’t do it as much goin up hill, but is still a problem then. If I keep on the accelerator it stays running. I cant figure out what the deal is and is absolutely driving me nuts. I appreciate your help.