I have a 94 TLC w/150K and I'm the original owner. My problem started a couple months ago when I checked the valve clearance and replaced the radiator and heater hoses. It started running roughas though on 4 or 5 cylinders. R&R the plugs and it ran fine for about a month, then it started to hesitate/ buck for a second as though the ignition was being switched on and off real fast. This would happen totally at random at different speeds, it could happen every day or every other day, but never at idle. Checked codes-NONE. Changed plugs, ran fine for about another month then same thing happened. Again no codes, replaced wires, cap, and rotor. this seemed to fix for 2 months and here I am again. Now it's getting worse it is hesitating/bucking for 5-10 seconds and speed will decrease to 10-15 MPH then it runs good. Still no codes. Checked resistance of distributer pickups & ciol per the FSM- check good. Any thoughts, comments or suggestions would be appreciated. Please help. The wife has threatened to take it to the Dealer...OUCH