1986 chevy suburban has no powery

[camaroguy89rs]

Hey everyone, I have a 1986 chevy suburban 350ci 4x4.. Ok the other day it just started running like shit, it has no power, i looked at the plug wires and 2 of them were bad so i changed them, didnt work, i changed the map sensor didnt work, sprayed carb cleaner in the carb and nothing checked the cap and rotor they were bad so i replaced them.. still running the same.. But the truck does have power when in idol, hit the gas and it screams.. all good, but as soon as i put it in drive and go to take off it has no power.. when i do pick up some speed i can floor it and it will go into over drive and have power.. Does anyone know what it could be? Also i redid the back brakes and there not too tight
Re tracking my steps.. I did the back brakes, took it to the car wash and degreesed the motor and under carrage then the next day the problem started.. I just got the truck 2 weeks ago

[bobss396]

Pop off the distributor cap, I bet you got water into it. Dry it out and you should be good to go. You may have gotten other things wet as well.

Bob

[big dwag]

Check for vacum leaks ,intake or hoses