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I'm working on my personal vehicle - 2002 Subaru Outback with the 3.0 H6 engine.
History: I picked up a few misfires when I did a Seafoam treatment via the intake. It was time to change plugs anyway so I did this and the codes went away. I also changed the fuel filter around this time per maintenance schedule. I also rinsed the engine with a garden hose this same weekend.
I know that is a lot of priors but the information may be relevant.
Current condition: an intermittent shake (feels like a misfire) at idle.
Fuel Trims: LTFT ~ 6-7%. Similar for both banks.
Clear flood crank: Sounded relatively even.
Happens at cold start but possibly more when warmed up.
Note these cars are MAP system (Speed density). They also do not have misfire counters per cylinder but there is some Mode 6 data that is hard to read but is somewhat indicative of an intermittent misfire.
Where should I head next? I do not have a scope right now but am ready to invest in one if it's necessary.
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