Chrysler has very little trouble with injectors. The engine computer should be memorizing a fault code related to a cylinder misfire if that is indeed what is happening. The best approach is to connect the hand-held computer to watch the sensor readings while the engine is idling. In particular, look for an unstable reading from the MAP sensor.
You should also check the engine mounts. If the rubber isolators are missing, or the two parts of the metal brackets are touching, engine vibration will be transfered into the passenger compartment. The clue is the engine will sound normal when you listen under the hood. Metal-to-metal contact of exhaust pipe hangers can do the same thing.
Also look for a sticking-open EGR valve. They only open at higher engine speeds when you won't notice the introduction of exhaust gas into the engine. When it sticks open at idle, the incoming air and fuel is diluted and will cause rough engine operation or stalling. The valve also should never open until the engine is warmed up.
Saturday, February 27th, 2010 AT 8:54 AM