intermittent check engine light & dealer can't find problem

http://www.mustang6g.com/forums/showthread.php?p=1725808#post1725808

Found it for You. Even has information from Ford Techs you can take to your dealer.

dev1360 said:

http://www.mustang6g.com/forums/showthread.php?p=1725808#post1725808

Found it for You. Even has information from Ford Techs you can take to your dealer.

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Very much appreciated!!!!!

Forums are truly great sometimes.

Looks like this one can be put to bed.

Per conversation with my persistent and professional Ford dealership "runner inside the intake port was flopping around loose, and if it was right then it should not be visible in this picture".

Thanks to this forum for help with the issue!!!

dev1360 said:

Check the intake manifold. A bunch of guys are having this exact same issue. It's turning out to be cracked manifold runners or IMRC valves broken. There's a thread here if you search around.

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Please note. This guy is a genius!!

I had the same issue with mine last week. Thanks to this thread, we had it figured out quickly. Dealer replaced the IMRC and, fingers crossed, so far she's running great.

MagneticPersonality said:

I had the same issue with mine last week. Thanks to this thread, we had it figured out quickly. Dealer replaced the IMRC and, fingers crossed, so far she's running great.

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I would not bet a lot on it, but as I remember, the air/fuel ratio display had a lot more noise in it before the problem was fixed. I think if I had compared that display to normal I would have seen a difference. Now at steady speed in top gear the ratio moves from 13.8 to 14.2 (+ -) , and I thought I remembered larger and more erratic swings previously, something like 12 - 17.

Mine is at the dealer for this same issue.

Good to know your issue has been resolved!

Curious though..who in here has had the crankshaft position o-ring installed to solve this P0300 CEL issue without any faulty IMRC?