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Cold Start Configuration - Large overlap


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Hi there,

Hoping for some advice on cold start adjustments I can make in the PC Link software to enable an engine with large overlap start off they without any throttle.

Currently I have to open the throttle a tad to enable the car to start when it's cold. I need to hold the throttle in this position to keep the engine running until its at around 30+ degrees, then it'll just idle on its own until it fully warmed up and idles perfectly. It seems no amount of adjustment to the post start enrichment table can resolve the issue of the throttle needing to be partially open. Engine just wants a lot of air flow when starting and running cold. Winding the idle screw in on the throttle body is not a solution, as this then provides too much airflow when its warmed up and impacts the idle. 

Is there and tuning corrections I can make, or do I simply need to g to an idle control valve or e-throttle to remedy this?     

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if you don't run anything that could help getting more air in (e-throttle or IACV) then what you could do is open more the throttle blade with idle screw and reduce significantly the timing at warm idle. like 15° less than what you currently have, and maybe still get 100rpm higher idle than before warm, but sustaining cold idle

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Yeah, what dx4picco mentions is your only option with no air bypass.  Quite often you still wont be able to get enough torque increase without extra air to overcome all the extra parasitic drag of cold oil etc though.

Set the idle ign control table to 3D with ECT Vs idle target error.  Have the throttle stop set such that you have about 0 to -5deg ign advance to achieve the target idle speed when warmed up.  Then from there see if you can maintain cold idle by adding advance alone.  

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