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- Joined
- Dec 16, 2016
- Messages
- 1,024
- Reaction score
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- 113
- Location
- Denver
- Vehicle Year
- 2009
- Make / Model
- Ford Ranger FX4
- Engine Type
- 4.0 V6
- Transmission
- Automatic
- 2WD / 4WD
- 4WD
Its a little hard to tell from the photos you posted, but it looks to me that it could be the exhaust valve is opening late. If the lifter is collapsing and not opening the valve properly, you should be able to see that with the valve covers off while turning the engine over by hand. You didn't say if that scope record looked the same for all cylinders or just on one, but if just one that is the one I would start with. The next thing I would look at is how much the rockers are moving since you could have a bad cam with a bad lobe (or several).
