i have a 01 ac 250 2x4 and lately it has been running horrible. we had a mechanic look at it and told us it was the intake valve, so we fixed that and it was runnig great(it was to tight). now, it is running realy rich and after a while the plug will be black. when u try to ride sometimes and give it some gas, it was bogg down, adn backfire and stall and it will not idle at all. also, when it is running ok, u will have no power. im only 14 and wiehg 110 and if i o up a steep hill and stop half way, and try to get going again it will barley go. any ideas???

 

All better now, Right?

 

yup thanks