Please Help! Datalog Uploaded Hanging Idle

OneSick99GT

Active Member
Nov 20, 2018
364
47
38
Dayton, Ohio
Hi,
Some of you know me from this forum but those of you who don't here is my issue. I've spent a lot of time troubleshooting this and I'm about to give up and have someone professionally tune my mustang. I've been working on this same issue since last fall just about every week. Shows you my patience to learn and figure this out. My GT currently idle's high for 2-3 seconds before falling down when shifting gears. However at times it will hang and not come down or will continue to go up. I'm clueless but do believe its more mechanical than tune related. I've exhausted just about every high idle, hanging idle forum solutions I can think of. The files I've uploaded on here shows Long Term and Short Term Fuel trims, along with, spark, Duty Cycle and lambda. There is also a couple other one's on there too. Hopefully someone can identify exactly what the issue is from datalog. I tuned it in open loop and got the tables perfect. Once I turned on closed loop and adaptive learning this is what I got. I've driven it quite a bit but I'm afraid of internally damaging the motor and need to figure out whats going on. I've calibrated my throttle body per specs of the manufacturer. I use SCT software and they have no support with their tuning program including no forum support so I'm stuck.
 

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Look at the idle valve duty cycle, its a decimal so if you multiply it by 100 you will get the % the valve is open. I cant tell in the log if you are revving the engine as i cant see TPS... The ignition advance is working to control the idle speed that i can see, when the idle is high the timing is retarded to bring the idle speed down. something is off in the load settings on the IAC follower?? table sorry not that familiar with the stock stuff.

The idle valve duty is the culprit.

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