If your voltage drops a lot, I'd have to check your battery and charging system, to begin.
If this is a high-mileage engine, I'd have to check cylinder compression. If very poor cylinder compression, your going to have trouble trying to get it to run correctly. There is not much load on the engine in park or neutral. With the engine in gear, there is a load on it.
Wednesday, March 19th, 2014 AT 12:24 PM