MIVEC Target?

[k4nnon]

Hey all its been a minute but I have a question about my mivec target vs actual numbers. Im wondering if im having issue somewhere or if these values look appropriate. Ill post up a casual driving log in the link as well as my current map. My values always seem slightly higher or slightly lower than target. Even at idle where target is 0 i get values jumping around. Is there something i should look at to get these values in line or an adjustment in my tune file? Any input or help is always appreciated. Thanks

06 evo9.

https://drive.google.com/file/d/1YztlGxBhlYcEoPRSmk_72WIGS6iA-ATB/view?usp=sharing 

 

E Cal 1..pclx

[Adamw]

Its actually not too bad, but could be improved with some PID tuning.  I notice your coolant temp only reaches a max of 70°C in that log, is that as hot as it gets or was it still warming up?  If its still warming up this log may not be representative of how it behaves when warm - the oil viscosity can have a big impact on VVT control.  I will suggest some changes once you confirm that. 

The small jitter at idle when target is zero is with the vvt disabled and sitting against the mechanical stop so that isnt going to be improved much.  I would just do the cam angle test>cal again when fully warmed up which may zero out some of that error.  

 

 

[k4nnon]

On 9/9/2022 at 5:21 PM, Adamw said:

Its actually not too bad, but could be improved with some PID tuning.  I notice your coolant temp only reaches a max of 70°C in that log, is that as hot as it gets or was it still warming up?  If its still warming up this log may not be representative of how it behaves when warm - the oil viscosity can have a big impact on VVT control.  I will suggest some changes once you confirm that. 

The small jitter at idle when target is zero is with the vvt disabled and sitting against the mechanical stop so that isnt going to be improved much.  I would just do the cam angle test>cal again when fully warmed up which may zero out some of that error.  

 

 

Hey Adam, Thanks for the reply. When the vehicle is fully warm and hot on a hot day my coolant temps will max about 190*F when at a stop light. While moving the temps are about 180*F or below. This day while taking the log, the outside temp was cooler so the vehicle only got up to the temps showed in the log while moving or stopped. Oil temps and viscosity could be playing a role. Im just not sure how closely the target and actual should be or if some deviation is acceptable. I did figure that some PID adjusting could probably settle this out, however i dont have much experience with adjusting PID stuff so i dont want to make matters worse or potentially damage anything. I may have to experiment with some very small adjustments and see what happens. Also I did see that my voltage compensation is currently turned off. Would turning that ON change what im seeing for the better? Or should i leave this OFF as is?

Thanks for the input as always!!!!

[Adamw]

It sounds like your thermostat is not working, you should have no trouble getting up to a normal stable operating temp regardless of ambient.  

As for the PID, you cant do any harm.  The first thing I would try is dropping the base DC as your doesnt look like it wants anything like our defaut 50%.  Set PID to custom and change the base DC to about 38%, see if that helps.  

[k4nnon]

On 9/11/2022 at 5:03 PM, Adamw said:

It sounds like your thermostat is not working, you should have no trouble getting up to a normal stable operating temp regardless of ambient.  

As for the PID, you cant do any harm.  The first thing I would try is dropping the base DC as your doesnt look like it wants anything like our defaut 50%.  Set PID to custom and change the base DC to about 38%, see if that helps.  

Hey thanks again for the input! I can check but im pretty sure the thermostat is fine. Car gets up to temp fine but i wanna say the temperature outside was only 60*F or so. With driving and the larger radiator i just assumed the cooler air did not allow coolant temps to be as high as a warm day. The temp out this morning is 60 as well so i will verify! Thanks for the input i will give it a try!!

[Adamw]

If the coolant temp is below the thermostat set point there should not even be coolant moving through the radiator. 

[k4nnon]

15 minutes ago, Adamw said:

If the coolant temp is below the thermostat set point there should not even be coolant moving through the radiator. 

Thanks that is a good thought and something i will check into. I just took a long log showing cold start/warm up and then the same drive to work that i took with the last log. Mivec actual and target are very close now with only changing the duty cycle as you mentioned. After the drive i let the car sit to watch coolant temps come up to see if i can rule out the thermostat is bad or not. Ill let you check it out and see what you think. Thanks for all the help and input i appreciate it!!

https://drive.google.com/drive/folders/1ctVovrKJeoLEI08LdHJdPDSUOxaj20xI?usp=sharing

24 minutes ago, Adamw said:

If the coolant temp is below the thermostat set point there should not even be coolant moving through the radiator. 

Almost looks like the thermostat is opening at 160 with its first opening event and then around 157/158 there after. Im looking at the warm up before driving. My fans are set to kick on over 180 i believe so does this confirm that the thermostat is working as should?

[Confused]

I'd expect the thermostat to be around the 82-88 degree C point, which is then the minimum you should ever be able to get to, even driving at high road speed/low load, no matter how big your radiator is.

 

Unless you do truly have a ~70 degree C thermostat, which would be unusual, I'd suggest that there's actually a mechanical problem here to sort out.

[k4nnon]

1 hour ago, Confused said:

I'd expect the thermostat to be around the 82-88 degree C point, which is then the minimum you should ever be able to get to, even driving at high road speed/low load, no matter how big your radiator is.

 

Unless you do truly have a ~70 degree C thermostat, which would be unusual, I'd suggest that there's actually a mechanical problem here to sort out.

Thanks for the input. There is a chance I built this engine with a cooler thermostat and forgot what it was. Ill take some more logs or even pull the water neck off to verify. Thanks again for the input!!