Just bought a 2000 2500 24 valve with 168000 miles on it. Truck starts great when cold, but is very hard to start when warm, have to crank repeatedly for long periods of time to start after reaching operating temperature. Truck runs strong, with no missing or hesitation. Done the key thing am getting the p1693 code in the odometer. Was told by dealership this is a defect in the pcm , and probably has nothing to do with the hard starting problem. Any help with this would be appreciated. Thanks Cliff. 02 3500 4x4 h. o. 6spd. , 00 2500 4x4 5spd, 98 2500 12v. 4x4 5spd. , 94 2500 4x4 5spd.