Check engine light on, vehicle running rough when idling. on 2004 Ford Freestar

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?

by in Ventura, CA on April 08, 2009
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9 answers 5 comments
ANSWER by , 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.
COMMENT by , November 18, 2010
Did you find the elbow part number? What was the price?
COMMENT by , November 18, 2010
COMMENT by , 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.
ANSWER by , July 14, 2010
ANSWER by , 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.
ANSWER by , 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.
COMMENT by , 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.
ANSWER by , 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.
COMMENT by , June 25, 2013
Hi, 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? thanks,
ANSWER by , 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.
ANSWER by , March 18, 2010
its your ignition switch
ANSWER by , 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...
ANSWER by , April 14, 2011
crank sencor is bad