I have a 2011 z4 n54, and when i come to a stop idle bumps up to 800-900 rpm's for a second. does anyone have any ideas?? no idiot lights all else is normal ?
so going home last nite come to a stop and idle is going up and down from 650 rpm to 1000 rpm just up and down but it stopped after the car warmed up. Is this the DISA ??
N54 does not use the DISA valves like the N52 and previous engines did. Could be multiple things but first to start with looking for a intake leak. Any loose piping, torn seals, valve cover cracked, vacuum lines. If unmetered air gets in the engine it can cause surging from the ECU trying to compensate for more air coming into the engine that what it measures.
