Hey I have a stock 78 B210 and im idleing very low almost to stalling and when I apply the gas pedal from a stop its takes a second to start going......I unplugged the spark plug from the cylinder next to the fire wall im assuming 4th and no change so I was thinking spark plug but that's fine and it's getting a lot of spark any ideas....? I was thinking its a vacuum leak or maybe a intake manifold leak , I haven't done a compression test yet but was just wondering if anyone had the same problem.....