617.952 stock, sealed ALDA, unknown miles ~290,000 estimated.

I'm not sure when this started as I had a rather high idle (~900) for awhile. I adjusted it back down to 780 (where it was steady) and just barely adjusted the rack damper.

Now it has an odd idle when in gear, but not all the time. It feels like one cylinder is either not firing or isn't firing hard enough. I can't quite describe it, but it almost feels like a car which only had four valves adjusted properly. (No... I've done three valve adjustments in the last month just to make sure)

It doesn't always do it, coolant and ambient temperatures have no effect. I've done a fuel filter change and will run it off of diesel purge in the coming week.

• no idea of injector condition (never changed or removed)
• smokes a bit, nothing too much (grey smoke)
• consistently runs between 26-28mpg
• starts right up every time without cranking (even when freezing outside)
• less than a quart of oil added every 5,000 miles

This is my daily driver, so I can't have any diagnostics that would have it apart for more than a day.

I can shift it into neutral and bump the revs up just a smidgen to even it out. But other times the idle is smooth as silk (while in gear).


Anybody got any clue?

I'll try to get it to do it again and get video up soon.

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