when i get in my truck it start okay when i put it in drive it okay when i press on the gas it is verry slugesh more you press down the slower it gets let up on the gas it will start going good but can not go over 50 miles hr i whent to auto sone they put a test on it everything cheked out okkay thank you for your time i did check the air filter its okay this is a two wheel drive i have a 351 engine gas my email is [email protected] 757-374-2110 thank you for your time my name is mark worton