Rough Idle?
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Fleet Owner
Joined: Aug 2010
Posts: 21,253
Likes: 1,656
From: Reynoldsburg, Ohio
Its a mixed bag without a lot of possibilities---less to wade thought, sort out and cuss about? 
I do need to confirm via my own scanner the MIL status---I do know it was triggered when I ran the engine very short term with all the ducting including the air filter housing off after cleaning the throttle body. Of course all that means is the system is working and the lamp in the cluster works.
Once this gets to my friend he should be able to narrow down the possibilities of the cause. Since the intake was R&I'd it could very well be breathing issues. Fuel pressure measured by the scanner is at least 40 PSI at idle so I think that's okay.
LTFT Bank 2 is @ 1.6, Bank 1 is 0.8. STFT's show good fairly quick switching at idle, not excessive or out of range from what I know of those values.
I really REALLY hope this isn't a compression issue as that would mean a warranty claim---I'd like to avoid that mess if at all possible.
I do need to confirm via my own scanner the MIL status---I do know it was triggered when I ran the engine very short term with all the ducting including the air filter housing off after cleaning the throttle body. Of course all that means is the system is working and the lamp in the cluster works.
Once this gets to my friend he should be able to narrow down the possibilities of the cause. Since the intake was R&I'd it could very well be breathing issues. Fuel pressure measured by the scanner is at least 40 PSI at idle so I think that's okay.
LTFT Bank 2 is @ 1.6, Bank 1 is 0.8. STFT's show good fairly quick switching at idle, not excessive or out of range from what I know of those values.
I really REALLY hope this isn't a compression issue as that would mean a warranty claim---I'd like to avoid that mess if at all possible.
Posting Guru
Joined: Jun 2009
Posts: 1,908
Likes: 20
From: Fort Smith, Arkansas
There are a lot of threads on here with people stating how new the plugs/COPs/boots are, then they start getting it apart and find a COP or spark plug cracked or torn boot. And it was the obvious thing all along but they worked around it in their head because "I just changed that __ miles ago". New parts can be bad right out of the box.
Thread Starter
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Fleet Owner
Joined: Aug 2010
Posts: 21,253
Likes: 1,656
From: Reynoldsburg, Ohio
There are a lot of threads on here with people stating how new the plugs/COPs/boots are, then they start getting it apart and find a COP or spark plug cracked or torn boot. And it was the obvious thing all along but they worked around it in their head because "I just changed that __ miles ago". New parts can be bad right out of the box.
The COP's are original to the van---about 140K miles on 'em but new boots and plugs which as we agree is meaningless often enough and yes we all "get inside our heads" too much thinking it can NOT be that simple.
I do have 8 brand new-in-the-package Motorcraft COP's if its one or more of those. I'd bet good money if its two or more they'll all get swapped out at the same time. I got such a good deal on these it'd be a no-brainer.
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