Hello to everyone here. I have a ranger 1999 that threw a code 1151. I brought it into the shop and they started by replacing all spark plugs and wires. They cleared the code and after 30 minutes of driving, it threw the same code. I also notice when stopped at a light, the engine (sometimes) runs real rough. Like it wants to shut off, but doesn't. What is wrong with my ranger?

__________________
Joe Sticklin

Ford Ranger 3.0L 2x4wd flareside 1999