Hello all. 2007 RL, roughly 195K on it. Recently it’s been acting sluggish on a recent vacation a few hundred miles away, As if you could feel the misfire ever so slightly. Thought it was bad gas, got fresh tank still did the same thing. Just recently threw the above codes, and it started misfiring more frequently. Checked the coils and determined they were good. I’ve heard some talk about the intake manifold getting clogged with debris and other possible causes, just looking to see if this is a common occurrence and where I should start. Thanks in advance.

 

Check for cracks on the hose. Could be dry and cracked. Could be an intake problem since it's all cylinders... You can tape it temporarily (do it well with strong tape and follow the folds well, and see if there's improvements. But a crack is a crack. Should be obvious.

 

I would try cleaning out the EGR ports throught the intake manifold to the EGR valve.

 

I had same issue once. Misfire and shaking at idle speed. Driving ok once rpm is over 1500. Replaced egr valve. No prob.