1986 Buick Park Avenue stumble at takoff

Engine Performance problem
1986 Buick Park Avenue 6 cyl Two Wheel Drive Automatic 800mil miles

car has new moter in it all parts hav ben replaced ign moduel coil packs wires plugs cool temp sen iat tps mat iac all relays every thing but the camshaft sensor and the crankshaft sensor some thmes I get a coad 42 est the cam and crank sensor some times the car will buck and stumble when I step on gas to take off or from idle it will hesatate then fine stop go to take off its will stumble or stall or no start with light poping then leve it maby ten mins or what ever then run like brand new car some times does this how do I know if its cam or crank sensor