[olopezm]

The faulty DPFE's are the metal silver ones so you might want to check that; however, I would focus on the EGR valve vacuum line and PCV grommet first.

The PCV valve should not definitely pop out just like that, so find a new grommet and replace it.

Follow the EGR vacuum line towards the back of the intake manifold. I had a problem with it and became undone. Make sure it's properly seated and preferably put a zip tie on it to prevent it from coming loose again. Other than that, make sure the EGR tube (the one that connects the EGR valve to the exhaust manifold) isn't cracked. If everything is OK I would suspect the DPFE might be at fault.

Misfire could be either the vacuum leak, clogged EGR passages (you would have to remove the upper intake to check that) or a faulty coil pack, which are also a known problem in our models. You can inspect the coil pack by removing it and looking at the back of it; if you se any cracks on it, then it's gone bad and you need to replace it. Although I recognize that a cracked coil pack would more likely cause misfires in two cylinders at once, it doesn't hurts to check.

Oscar.