I have a 96 GTX. It starts right up, when I give it gas it will take off fast but bog and stay at 2000rpm with wot until I let off the throttle and then it's back to idle. After about 5min of warming up it will run perfect. Its like it has to warm up. If I turn it off for 5-10min it repeats that same thing...I've cleaned carbs, rave valves, new battery, new spark plugs. Any advise would be great!!