IDLE Control, Surging - V6 - Supercharged

[L67Hulk]

Hi all,

I am having difficulties with finding a stable idle configeration and was hoping someone could have a look at my log files.

I have a large throttle body so air metering is quite responsive so when trying to find a smoth transition from idle can be tricky, however im sure that my idle settings are the main cause.

https://drive.google.com/drive/folders/1xwxQa122D7Aca7QGivojmc0q2JUG_j6b?usp=sharing

 

 

[castillaricardo]

Your Idle Base Position is set to 0 across the board, but the min clamp setting is set to 10%, which is how some air is entering the engine. You should set the base position table to a value that lets the engine idle at your wanted RPM. 10-11% seems close for your engine. Also, your idle ignition settings seem odd. Mainly the Idle Ignition Table seems like it was setup for a G4+? Try using a single target of around 10BTDC, and let the ECU do the rest. You shouldn't change the target with RPM error, the ecu will do that with the PD algorithm. Another item is that the engine was idling lean by the end of the log, around 1.1 Lambda, so it needs more fuel. A lean mixture affects idle quality.

[L67Hulk]

7 minutes ago, castillaricardo said:

Your Idle Base Position is set to 0 across the board, but the min clamp setting is set to 10%, which is how some air is entering the engine. You should set the base position table to a value that lets the engine idle at your wanted RPM. 10-11% seems close for your engine. Also, your idle ignition settings seem odd. Mainly the Idle Ignition Table seems like it was setup for a G4+? Try using a single target of around 10BTDC, and let the ECU do the rest. You shouldn't change the target with RPM error, the ecu will do that with the PD algorithm. Another item is that the engine was idling lean by the end of the log, around 1.1 Lambda, so it needs more fuel. A lean mixture affects idle quality.

Thanks for this, i'll make some changes and see how i go...:-)

[L67Hulk]

 @castillaricardo 

would you be able to have a look at my log file, I have made changes as suggested and I am still experiencing rev hang, it doesn’t happen all the time mainly when I touch the throttle from idle, I am also experiencing some excessive popping (ignition retard) when off the throttle would this be caused by the idle settings?

If you could point me in the right direction that would be appreciated.

Rob.

https://drive.google.com/drive/folders/1xwxQa122D7Aca7QGivojmc0q2JUG_j6b?usp=drive_link

[Adamw]

You have stepper reset set to set to key-off, but no ECU hold power set up so the idle valve is never going to reset.  The idle valve is going to be in a different place everytime you start it and the ecu has no way of knowing where it is.  If the main relay control has not been wired as per one of the hold power schemes then your best option would be to change the stepper reset to "key on fuel lockout", it will then do the reset when you switch on ignition and will apply a fuel cut to prevent it starting if you attempt to start while the reset is occurring.  So, turn the ignition on, wait a couple of seconds for it to reset before cranking.  

Your base position will likely need re-tuning after changing that.  

[L67Hulk]

26 minutes ago, Adamw said:

You have stepper reset set to set to key-off, but no ECU hold power set up so the idle valve is never going to reset.  The idle valve is going to be in a different place everytime you start it and the ecu has no way of knowing where it is.  If the main relay control has not been wired as per one of the hold power schemes then your best option would be to change the stepper reset to "key on fuel lockout", it will then do the reset when you switch on ignition and will apply a fuel cut to prevent it starting if you attempt to start while the reset is occurring.  So, turn the ignition on, wait a couple of seconds for it to reset before cranking.  

Your base position will likely need re-tuning after changing that.  

Thanks @Adamw i'll make the changes and let you know.

once again appreciated :-)

[L67Hulk]

Ok guys, I managed to make some good changes to my idle issues but I’m still struggling to find the sweet spot., would anyone be able to view my log files and provide some feedback on what areas I need to focus on to fine tune the idle control. When viewing the file, I made some changes on the fly to improve the idle. the last part of the log shows the rev hang with idle condition stating active. If I force the engine to almost stall idle control will engage would this be driven from the map lock out settings or rpm lock out? Could there be something else within my tune that is driving the rev hang? Thanks in advance

https://drive.google.com/drive/folders/1xwxQa122D7Aca7QGivojmc0q2JUG_j6b?usp=sharing

[Adamw]

The log shows the idle valve is fully closed.  So either the throttle is too far open, the stepper is not homing correctly, or it is losing position, so the ecu only thinks it is fully closed, but it is actually not.  I would expect to see idle position around at least 20% open when hot.   I would change the integral gain to 0.5 as 1.25 is possibly forcing it to move faster than it can actually move.  

Your idle ignition proportional gain is also very high at 15, typical is 1.0.

[L67Hulk]

12 hours ago, Adamw said:

The log shows the idle valve is fully closed.  So either the throttle is too far open, the stepper is not homing correctly, or it is losing position, so the ecu only thinks it is fully closed, but it is actually not.  I would expect to see idle position around at least 20% open when hot.   I would change the integral gain to 0.5 as 1.25 is possibly forcing it to move faster than it can actually move.  

Your idle ignition proportional gain is also very high at 15, typical is 1.0.

Thanks Adam, I made those changes and it has improved not great but better, I will check the idle stepper is getting "Home" the throttle blade is fully closed, I'll check for any vacuum leaks as this could be contributing.