Based on your description of "chugging", and especially the mileage, it sounds like you have a fuel pump that is intermittently not starting up. On Chrysler products, they will rarely quit once they're running, unlike the GM pumps that often leave you sitting on the side of the road. When the brushes in the pump motor become worn on Chrysler pumps, they often don't make good enough contact for the motor to run unless you bang on the bottom of the tank to jar it a little. That is likely what happened when the van was rocked. Intermittent electrical connections will act the same way but that would cause the engine to stall at times while driving too and you haven't noticed that. The chugging you mentioned is due to the engine running for a few seconds on the pressurized fuel stored in the hoses until that pressure is depleted. Sounds like it's time for a new pump. The next time it doesn't start, listen for the hum of the pump motor. It should only run for one second after the ignition switch is turned on, then again during cranking. If you have to, listen under the tank while a helper turns on the ignition switch.
Monday, July 5th, 2010 AT 1:17 PM