Allow me to help in diagnosing your vehicle! If I helped make sure to hit ACCEPT button so as I can get credited.In neutral the engine has a rev limiter that will kick in causing it to miss which is normal. Does the engine missfire when you are driving? The engine is common for ignition coil failure, You will have to have the codes pulled from the computer to identify the fauly cylinder. If it does not missfire but still not accelerate the concern can be a restricted fuel filter,faulty fuel pump,restricted ctalytic convereter. These are possibilities with this vehicle.
It does misfire if I try to accelerate too quickly, or if I try to accelerate above 50 - 52 mph.