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Check engine light on, vehicle running rough when idling.

(2004 Ford Freestar)
in Ventura, CA on April 08, 2009
The check engine light came on while driving and the van started running rough, ie revs fluctuating from around 600 rmps to 1200 while idling and it will stall if revs are not increased by keeping foot on gas. When up to speed, it seems to run fine. Just had a tune up done a few months ago, new spark plugs etc. It does have almost 125,000 kilometers on it. Any idea what the problem might be?
Displaying 9 answers & 5 comments
Popular Answer
on October 05, 2010
Just had the same issue with our 2004 Freestar. The failure is a rubber vacuume hose elbow that enters the upper intake manifold. The hose elbow connects to a longer formed plastic hose that runs over to the front valve cover and connects to the PVC valve in the valve cover. The rubber elbow had a hole in it allowing for a vacuume leak. Engine runs okay at speed but is very rough at idle.
on November 18, 2010
Did you find the elbow part number? What was the price?
on November 18, 2010
on December 01, 2010
I had that problem with my freestar, goodyear fixed the pump for about 65 bucks, but not even a month later the lights back on, now they are saying I need two parts and it'll be about 1500. On top of that they said my alignment is off and causing my front two tires to ball (of course now making my tires not covered with the warranty, I just got new tires less than a year ago with them) and that's another 800.
on July 14, 2010
on April 08, 2009
Do you know what codes are stored in the engine control module? With that information, you can really get a better answer.
on May 02, 2011
I had the same issue and it is a defect hose. This was also mentioend in some of the previous replies.
The Ford spare part # is 3F2Z-6758-DA. This part can be installed easily.
on April 10, 2012
Same issue, same mileage. What the hE@$? Did they build this part to fail or what. Just glad it was a cheap fix.
on January 01, 2011
I had a similar problem and am very happy to say the fix was the rubber elbow on the PCV line at the intake manifold. Just fixed it today and have a smooth idle.
on June 25, 2013
I can see I have the same issue with the pcv rubber elbow... I see the part number listed here too but is the part number for the entire hose with the elbows? Or are the elbows sold separately? Someone told me the elbow is fixed to hose and I cannot change elbow alone.

Any help?

on November 03, 2009
You really need to go to town hall on and look up 2004 Ford Freestar engine problems and be amazed. We need a recall.
on August 23, 2010
Mine started that about 2 weeks ago, Just took it to Good Year and put on Analyzer. My PCV Tube Sensor is Leaking air..Manufacture part so I have to order it...
on April 14, 2011
crank sencor is bad
on March 18, 2010
its your ignition switch
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