[Buz Lloyd]

My 2003 Ranger 3.0 V-6 with 5x2 with 55K miles has begun bucking intermittently when under load (accelerating up a hill, etc.). Can go several miles between occurrences. After several instances, check engine light came on and the OBD produced two codes: P1336 and P0340 which relate to the crank shaft and cam shaft position sensors. Should I replace one or both or is futher diagnosis warranted? A local garage wants $200 in (further) diagnostic fees before they will do any repair work; they object to "throwing parts at it". Any insights on how to best proceed?