Boldie Posted January 9, 2021 Report Share Posted January 9, 2021 Hi people, I have a issue with idling. Motor cold starts fine and warms up good. Sometimes after coming down of revs or if motor is turned off and then on it won’t hold an idle. overview of vehicle: competition 4x4 run a L98 with a kelford J cam. Computer is a Storm G4x using a “standard” ac15 idle control valve. Cable throttle body. No o2 or maf sensors. no speed sensors. I hope I have given enough info to get the ball rolling. cheers Quote Link to comment Share on other sites More sharing options...
koracing Posted January 9, 2021 Report Share Posted January 9, 2021 No o2 sensor? So no wideband showing AFR? Can you post up a copy of your tune? Quote Link to comment Share on other sites More sharing options...
Boldie Posted January 10, 2021 Author Report Share Posted January 10, 2021 It was tuned with an o2 sensor. here is the tune file hope you can open it? Boldie back up.pclx Quote Link to comment Share on other sites More sharing options...
koracing Posted January 12, 2021 Report Share Posted January 12, 2021 Without an o2 sensor now and a PC datalog showing the problem, there's very little information to go on here. The stepper idle control can sometimes have that issue if it's not properly set and the ecu hold power setup is correct. Your hold power keep alive time is set to 0.5sec - it's probably necessary to keep it on for a longer period than that to rehome the idle stepper motor - maybe try upping that to 10 seconds and see how that does. Quote Link to comment Share on other sites More sharing options...
Adamw Posted January 12, 2021 Report Share Posted January 12, 2021 Base position table and idle ignition control is set up wrong too. Please give us a log of it starting from cold and left idling until warm. Quote Link to comment Share on other sites More sharing options...
Boldie Posted January 14, 2021 Author Report Share Posted January 14, 2021 Data logs of warm up and when issue is happening warmup.llgx problem.llgx Quote Link to comment Share on other sites More sharing options...
koracing Posted January 14, 2021 Report Share Posted January 14, 2021 First I would update the firmware. It's very hard to tell what's going on with how it is tuned without any air/fuel ratio readings. Do you know if it's going lean or rich when it stalls out? Can you install a wideband and log with that installed? If the idle oscillates as much as it is but then ends up in an area that wasn't well tuned that can certainly cause the idle to not recover. What happens if you increase the idle stepper position warm? I see you have it set to bipolar reverse stepper - is that correct for your stepper motor? Without knowing that I'm unsure if the values you have for base step position is good or not - the steppers I've seen in the past ran low values when idling higher, and high values when idling lower, but I think those were standard orientation steppers. Your hold power at 0.5 seconds isn't likely long enough to rehome the stepper at key off as I mentioned before, so try increasing that. The proportional and derivative values for idle timing control are both much higher than I've typically seen (usually 0.5-1 versus your values of and 30/20). Your Integral on the idle valve is 5 which may or may not be too agressive, but your idle control MAP limit of 64kpa is being exceeded when the rpms fall and the idle control stops trying to catch the motor as well. I feel like resolving this issue is going to require some tuning to get right as opposed to just a single changed setting or two. Quote Link to comment Share on other sites More sharing options...
Adamw Posted January 15, 2021 Report Share Posted January 15, 2021 (edited) Try the attached file, I have fixed up some of the points I mentioned earlier so it should be closer. As per KO's advice, please update firmware to. Then load this map in and do us another log. Boldiebackup new idle.pclx Edited January 15, 2021 by Adamw typo Quote Link to comment Share on other sites More sharing options...
Boldie Posted January 17, 2021 Author Report Share Posted January 17, 2021 firmware is as up to date as i can get it. Here is the data log of adamw's file. newidlelog.llgx I noticed that during warm up it it doesn't like any throttle (motor snuffs out) Quote Link to comment Share on other sites More sharing options...
Adamw Posted January 17, 2021 Report Share Posted January 17, 2021 You are still on old firmware, 6.17.8 The latest is 6.19.** Download the latest PC Link from the Link website and have another go. Your alternator is not working in the log, battery voltage is only 11.6V at the end of the log. The idle valve is near fully open the whole time so the throttle stop may need to be opened a little more. The idle settings will not affect its ability to "take throttle", that is a warmup tune issue. Fix up those points and do another log. Quote Link to comment Share on other sites More sharing options...
Boldie Posted January 18, 2021 Author Report Share Posted January 18, 2021 Firmware updated. Alternator seems to be working now. Idle screw up to 0.5% log seems to be too big to upload? Quote Link to comment Share on other sites More sharing options...
koracing Posted January 18, 2021 Report Share Posted January 18, 2021 You have limited space on these forums to upload files. You can either delete something you previously uploaded, or use drop box, google drive, or similar to upload online and share a link. Quote Link to comment Share on other sites More sharing options...
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