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5.7ute
October 19th, 2008, 06:43 PM
Now the summer temps are back I need to address an old issue that has been asked a few times but never solved.
When coming to a stop with the aircon on my engine will stall.The only added air tables that I can find are B4301 & B4302 fan iac correction. Are these the only tables we can use to sort this issue or am I looking at this the wrong way.
For instance is there hidden tables related to airflow we need to address in a different way.
Car is a cammed M6 with 25% udp.

macca_779
October 20th, 2008, 02:34 AM
I've had similar issues in the past with A/C doing this. With mine it wasn't always stalling but what it would do is dip low and often hunt a couple of times before settling. With the fan tables you mention. I've only ever found them useful for the initial tip in activation of A/C. Almost like they prepare the engine for the extra load but don't really do anything while its already there.

What I have done to fix it in cammed cars is just revise Follower so it decays quick initially then via an increasing multiplier value at 1200rpm and below in B4316 cause it to hang for approx .3sec before dropping to an 850rpm idle.

Its also possible that you need more cracker air. I try and keep mine to a minimum but what I have now is approx .15 added when braking and approaching near stationary speeds.

My advice is to just log follower and cracker air to make sure its actually being applied for when you need it. Make sure its behaving how you want during stationary revs for the follower side of things and from there move on to cracker settings. Just remember that decay rates are quite small in value so just work in percentages when trimming them.

5.7ute
October 20th, 2008, 10:36 AM
Thanks macca 779 I will give this a go.:cheers: