u/ID-SonGoku

MazdaSpeed 3 bucks only on cold start, then runs perfect (P2006)

Hey everyone,

I’ve been dealing with a bucking issue on cold starts with my completely stock MazdaSpeed 3 (no tune, no mods) for a few months now.

At first, I got a P2006 code that popped up. I cleared it without really thinking much of it. Over time, the car started to occasionally buck on cold starts, but it was intermittent.

However, for the past ~2 weeks, it now happens at every cold start.

The behavior is always the same: it bucks for about 10–15 seconds right after startup, then everything goes back to normal. Idle settles down and stays rock solid, the car pulls hard, the engine sounds fine, and I don’t have any other issues while driving.

The only other code I have besides the P2006 is a P0455.

I’ve already changed spark plugs, coils, MAF sensor, and cleaned the throttle body, but the issue is still there.

Has anyone seen something like this before? Could the P2006 / intake runner flaps actually cause this? Thanks in advance 🙏

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u/ID-SonGoku — 3 days ago