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Idle oscillation when over speed lockout


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I've been able to improve idle a lot by following a few advices on this forum. 

When I'm over the speed lockout (status = hold speed) the idle oscillate from 1700 to 1300 until i reach the speed, then it stabilizes very nicely. Can't seem to find what is controlling idle when above the speed. Attached the tune and a log I did.

tx, 

 

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You need to do a PC log as you havent logged any of the relevant parameters.  But - in hold mode the ecu is not controlling idle at all.  I suspect your oscillation is coming from over-run fuel cut turning on/off.  Turn it off as a quick test.

 

Edited my comments about the folder label - that was due to a beta PC Link version I was using.

 

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Looks like it was the fuel overrun, turning it off fixed the issue. I rise the RPM deactivation to 2000 RPM and it fixed the issue.

One last issue trying to fix, when the car is really hot, blip will get the idle down to 600-700rpm almost staling the car, when the target is 1100. I attached 2 PC log showing this. The PID gets to max timing (35) quite fast the idle is still dropping, then throttle starts opening up to 5% then still dropping, then it starts getting back to the target. 

tx for the help

 

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There is quite a bit I dont like in your map attached earlier, for instance the E-throttle is set up with no integral so it is not following target.  

Can you attach your current tune and I will change a few things.

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I really appreciate the feedback and the help. Got a tuner setup the car this summer, but I'm in the process of going over the map and improving it. I just disabled the warm up ECT and started to setup the charge temperature instead. I've disabled the wastegate, reduce timing on boost (via the IAT ignition trim) and disable close loop fuel while I'm adjusting the fuel map. There is an offset with my current AFR gauge that I account for in the AFR lambda target (1.03 lambda = 1 on the gauge), I'll fix that over winter with a new CAN controller. Don't hesitate if you have other recommendation on the map.

 

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I did a few more logs to check what is happening with throttle with the car not running. Seems that TPS is always a bit off compare to the target. I'll investigate further and test a few things later. Here are 2 more logs if you have suggestion. Throttle body is from a WRX 2008 (one that goes with the plastic intake manifold). Default configuration from the v10 base map doesn't use I either, not sure if it's on purpose. 

 

 

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The sample maps were vaguely converted over from the G4+ ones but seeing as the PID setups changed between the ECUs I didn't have any solid new values to put in, if you get it all tuned nicely and don't mind sharing your PID values I can update the values in the sample map.

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I have made some changes to your map based on our V11 test car, I assume most of the mechanical bits are probably similar.  The base position table is a bit of a guess as ours idles at 800RPM whereas you are targeting 1100RPM.  So load this map in, log a cold start with car idling until it is up to operating temp, that will give us enough info to fix your base position table.  

You can use the file compare feature to see what I have changed.

1168819401_Simon-Gagnon-SubaruSTIV10G4XXtremePlugin-V1-5-0fueling New idle.pclx

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Awesome, it works really well. I've updated the base position table following what throttle position the car was using at each ECT temp. Logs for warm up is too big to attach, sending throttle test engine off logs, idle test once engine is at temperature and a hot restart. Also including the updated map.

PC Datalog - 2020-10-21 7;16;34 pm engine start.llgx PC Datalog - 2020-10-21 7;14;34 pm idle.llgx PC Datalog - 2020-10-21 6;57;07 pm throttle test.llgx Simon Gagnon-Subaru STI 2.35 G25-660 G4X-V1-5-2 throttle PID test Adam Value.pclx

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