Hi idle speed on cold start

[csracing]

I'm pretty happy with my idle, return to idle and overall performance of my current tune.

One of the remaining "bugs" I have yet to figure out is a very high, hanging idle on cold start. The engine will start and run at ~2000rpm for 10+ seconds before it starts to settle into prescribed idle speed. Total time before it gets to within 200rpm of desired idle speed is north of 30 seconds.

I've gone through and looked for any "adders" and the only idle speed adders I've found relating to cold start max out at a 150rpm adder. Fuel base cold table is .85 and .90 with ECT is <20 degrees. All the other load cells below .6 are .98 or 1.0 lambda. Fuel Cranking vs ECT is all 1.0 at >20 degrees.

Timing tables are as follows.
Max cold start: Entire table is 10 degrees.
Spark Max cold start adder vs rpm vs load: load of .10 is 40 degrees across the range. 24 degrees below 2750rpm and all remaining loads.
Idle spark is 34 degrees at 0 degrees ECT and below, then 10 degrees in normal operating range.
Min Idle spark is zero.

Thoughts? I found a thread from 2007 that talked briefly about this issue, but there were no clear answers or follow up from the poster stating that they fixed their issue.

Thanks
CSR

[Eric@HPTuners]

Post your file please.

[csracing]

I cut the values down in the idle air multiplier table and the problem has gone away. I've looked at that table a dozen times, but never really thought about it.

Most of the cold start multipliers were north of 2.5. They are now set to 1.25 and all is good.