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Hi folks, just trying to refine a tune on anew engine - running MS3ProPnP on a turbo 1.8. All the WOT stuff has been done at the dyno, now we are on to the idle. Check out this weird oscillation that happens immediately after the engine catches. This oscillation is at its widest when the car is cold, and almost disappears when it is hot:
The engine catches at 14 secs on the log, then at 15 secs it enters into a wide, slow oscillation until 30secs, where everything is fine. My questions are:
1. Am I right in thinking that from 15-30 secs on the log, it is not yet in Closed Loop Idling?
2. Does it enter Closed Loop Idling at the 30 sec mark when the Warm up correction ends? Or in other words, how can I tell when CL is on?
3. Are the only tables in “action” from the 15-30 sec marks the IACValve target starting position, the After Start Enrichment, or the Warm Up Enrichment?
4. If so, which one of the IACV target, ASE, or WUE should I be looking at to stop the oscillation?
Suggestions would be much appreciated