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IMPORTANT: enter the case-INsensitive alphabetic (no numbers) code AND WRITE SOME SHORT summary of changes (below) if you are saving changes. (not required for previewing changes). Wiki-spamming is not tolerated, will be removed, so it does NOT even show up in history. Spammers go away now. Visit Preferences to set your user name Summary of change: [http://megasquirtavr.sourceforge.net/manual/Detailed.Control.Idle.html#Config [Manual: Detailed.Control.Idle.Config]] If the engine spins up too high RPM after cranking and takes too much time for iac-dc (check your logs in spreadsheet or logviewer!!!) to start to decrease, your iac_integral_inc_limit is too high. If that does not lower the idling speed, then check that the 'TPS value for idle threshold (%)' -> (menu Extras -> Idle Settings General -> Idle Settings page in Megatune) has higher value than the actual Throttle Position value when throttle is closed. ---- '''Stalling engine''' If the engine has tendency to stall, than maybe the iac_integral_dec_limit is too high. But remember there can be MANY other reasons for this to happen. The MembersPage/MarcellGal/EngineSwap is a weak 1.6L engine. It '''often stalled with air-conditioner. The solution was to make the control authority as narrow as possible''', with smallest iac_integral_dec_limit and iac_integral_inc_limit values. Tuning warm engine first (the iac coolant dependent reference positions for lower coolant temp can only be tuned afterwards). This car has stepper iac, but same applies for PWM iac. Eg. the engine needed * '''iac position=29''' when AC and lights were off ('''without load''') * '''iac position=41''' when AC and lights were on ('''max load''') ** the AC is much more significant load, the lights is only 1 iac position or less I set the '''iac reference position''' (at max coolant temp) to decimal '''38'''. * I decreased iac_integral_dec_limit until the engine cannot regulate without load, that is iac position=30 resulted in slightly raised idle (iac_integral_dec_limit was appr 24 decimal in my case, but this also depends on integral value) * I decreased iac_integral_inc_limit until the engine cannot regulate at max load, => iac_position=40 cannot maintain the idle target (iac_integral_inc_limit was appr 6 decimal, but this also depends on integral value) Obviously, I increased the limits slightly (from 24,6 in the example to 25,7 or maybe add some more margin and 27,8). This * narrow iac authority-range * and setting the reference position a bit higher than the middle, as 38 is higher than (29+41)/2 fixed the problem of the annoying frequent stall with the air-conditioner on. ---- I have suggestion for little change regarding '''IAC follows tps when not idle'''. Now IAC position jumps to reference table value when not idle. It cause some transitional jerk if real IAC position is some % or steps less than reference. There can be two solutions: *follow from current position *stay at current position Choosing to '''disable''' did not help much. In addition if turbo used and intake end of valve is not connected post turbo, there is no way to close 2-wire BOSCH PWM valve. It opens in "limp home" mode and cause boost leak. Suggestion: *move to definite position. Slow if little throttle, fast if more. MembersPage/GintsK ---- Back to GenBoard/Manual/Config Back to GenBoard/Manual ---- See also: * IdleControl * IdleControl/HardwareFaq * IdleControl/IdleValveStepper * IdleControl/IdleValvePWM ---- Optional: Add document to category: Wiki formatting: * is Bullet list ** Bullet list subentry ... '''Bold''', ---- is horizontal ruler, <code> preformatted text... </code> See wiki editing HELP for tables and other formatting tips and tricks.