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sly · 05-05-2016, 02:14 PM

I have a 2016 Limited manual with a Cosworth 1.0 EcuTek tune. Mine does it too when the A/C compressor is on. If I come off the highway and shift into neutral, the idle will drop to about 500rpm and shudder a little. It doesn't do it very much when standing still and doesn't do it all if the A/C is not running.

So I don't believe it's just a tune issue although it's possible that Cosworth did not compensate for it. Maybe it can still be tuned out.

I wonder if @Matt@Cosworth has noticed this on any other Cosworth vehicles. Is the problem in ECU tuning or is it a mechanical issue? Maybe the little 2.0 is just not strong enough to quickly compensate for the A/C compressor cycling.

05-05-2016, 02:14 PM	#26
sly Senior Member Join Date: Dec 2015 Drives: 2016 Cosworth 2.2 BRZ Location: TN Posts: 335 Thanks: 88 Thanked 198 Times in 124 Posts Mentioned: 10 Post(s) Tagged: 0 Thread(s)	I have a 2016 Limited manual with a Cosworth 1.0 EcuTek tune. Mine does it too when the A/C compressor is on. If I come off the highway and shift into neutral, the idle will drop to about 500rpm and shudder a little. It doesn't do it very much when standing still and doesn't do it all if the A/C is not running. So I don't believe it's just a tune issue although it's possible that Cosworth did not compensate for it. Maybe it can still be tuned out. I wonder if @Matt@Cosworth has noticed this on any other Cosworth vehicles. Is the problem in ECU tuning or is it a mechanical issue? Maybe the little 2.0 is just not strong enough to quickly compensate for the A/C compressor cycling.