Check engine light indicated the engine was running lean on one side. After searching here and on the web I discovered others that tried everything and then finally changed the LOWER INTAKE MANIFOLD GASKET and solved the problem.

Why does Ford use plastic intake manifolds? What Cheap !@#$'s!!! I'm guessing this means they can't use a lot of torque to tighten the manifold to the engine, therefore, they need to use rubber o-rings to make the seal between the manifold and the engine. RUBBER O-RINGS!!!! C'mon Ford. Does the engine get hot??? Maybe rubber isn't such a good material to put right next to the engine to make a very critical seal. No wonder they don't stand behind their engines, they build them so cheap there is no way they can expect them to run to or past 100K miles. Rubber breaks down over time, just look at the rubber trim around your doors and windows. Sure Ford is going to say its special rubber for hot situations. Sure it lasts thru the warranty period, but they don't care after that. Are these engines disposable? My toyota ran to 240K miles and was still going when I sold it. No wonder Toyota's kicking everyone's butts. Why would I buy another cheap Ford???