Troubleshooting: Rough Idle with Noise
Here are the details:
I've got a 2010 Jeep WK 3.7L with about 65K
I picked it up used 5 months ago and about a month ago a noise developed under the hood.
(A) Rough idle and vibrations (evident in cabin and under hood)
(B) Tensioner bobbling/movement
(C) Intermittent rattling noise when engine is cold or warm at idle (drive, park or neutral)
(D) Idle is definitely smoother in park but still shows symptoms
(E) No fault codes to date
(F) steering wheel and pedal noise (could be paranoid now though)
(1) I replaced the tensioner assembly
Dealership service shop recommended and completed:
(2) replacement of spark plugs
(3) replacement of PCV
(4) flash of PCM
(5) flush of fuel system
The engine needed the (2) through (5) tune up because to my knowledge it wasn't done but it didn't resolve the issue.
The noise may be the tensioner but it's hard to isolate. I've suspected any of the pulley components due to the tensioner bobbling. When I remove the drive belt the noise does seem to go away (might be the tensioner making the noise). Regardless I don't think the tensioner is the problem (because I've replaced it)... I think it's a symptom of a different issue. Some of the pulleys aren't as smooth as others but none of them are locking up.
The sound isn't evident when accelerating or really driving at all so I feel like it's not an internal engine issue. The excess vibration challenges this thought though.
Any and all help is appreciated. Thank you.