Quote:
Originally Posted by andrew20195
Subaru believes the issue is related to a/c compressor cycling.
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That lines up perfectly with the idle dips I've been having. With AC on, coming to a stop after engine braking, it seems to not expect the AC to kick on so when it does the idle will dip, occasionally requiring the ECU to slam the spark advance to full, leading to some momentary spark knock. I do note that if I blip the throttle, it stays in elevated idle long enough to come to a stop and not do it until I've been sitting stopped for a bit.
I also note that the tach seems to go into a different mode during these. The idle will dip and the tach will lag, then move to a twitchier, faster mode before settling back down once idle speed has stabilized.
No AC means no dip, but I live in GA, so that's not often an option.
Think I'll head to my dealer.