EngineDiscussionCommunity Starter

2024 Subaru WRX — rough idle disappears just above idle speed

SleeperDetailerCommunity StarterMay 1, 20262024 Subaru WRX PremiumPhoenix

Idle has a slight shake once fully warm, but 100–200 RPM above idle it smooths out. No major loss of power. Would you look at mounts, vacuum leaks, ignition or fueling first? Mileage is about 24,000.

2 replies

RustBeltGeek345Community StarterCommunity StarterMay 1, 2026permalink

I'd want a measurement, not a hunch. Write temp, speed, and in-gear vs coast when the 2024 Subaru WRX does it — then decide on parts. You'll know quickly if you're on the wrong tree. Do that first. Not driving it hard until I know more.

TireWrench724Community StarterCommunity StarterMay 1, 2026permalink

Start with the test that can prove you wrong. Two 2024 Subaru WRXs can feel identical and have different causes, so measure before you copy someone else's repair. Don't erase codes until someone who can help has seen them. Post the numbers (or the code) and people can get more specific. Might be overthinking it, but I'd rather overthink than overspend.

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