I was coming out of a stop and my car started shaking when I would try to accelerate, and running poorly. The engine light had been on for about a year with not really any signs of any trouble, other than slight jerking when accelerating out of a turn or a stop. But not very much. It starts fine, and it idles in park. But I can't give it much gas because it shakes more the more gas I give it. It struggles going uphill because of this, and I can't really go faster than 30 or 35. I haven't drove it since driving it back home when the trouble started. Could this be something simple like the crankshaft position sensor or bad spark plug? Or does it sound more like a major transmission or fuel line problem?