I have a 1998 Dodge Ram 1500 3.9 liter V6 2 wheel drive . When I turn on the truck the idle is inconsistent and when I'm driving down the road it runs smoothly and then chatters quite a bit, almost like you're driving over a washboard dirt road. It stops and starts then stops and starts again with the time Gap in between each instance varying from one second two maybe eight seconds. There was a dash light on for the leak detection pump but that is not on right now because I left my lights on in my battery died. Any ideas or help would be much appreciated.

 

How many miles on it? Would be nice to see if there are any codes. Possibly a worn timing chain. I guess start simple. Air and fuel filters, spark plugs, cap, rotor. Then sensors, O2 and crankshaft. I'm just guessing, I'm not familiar with that engine. Someone else will help you more. I don't know if the V6 has the 2 piece intake or not. Could be a bad plenum gasket if it does. There would be a puddle of oil in the bottom of the intake. Look through the throttle body (or remove it).