[tom3]

First thing would be to pull off the egr valve. These are noted for getting a chunk of carbon in them and this makes for rough running. Just under the air intake hose on the front of the intake, round device sticks out at an angle upward. Then pull the top of the intake and look for gas pooling from leaking internal fuel lines. Nine small bolts and a couple wire connections will get it off, this is only the upper intake. With the intake off you can also turn on the ignition and watch closely for gas spraying, very high pressure so it is a very fine mist. Those plastic fuel lines are also noted for this.