Lambda leans when turning A/C on

[tbase]

Not sure what that I missed but Lambda gets lean (from 1.0 to somewhere 1.3) on idle when I turn A/C on. Please advise. 

 

 

AC Lean.llgx AC On LEAN.pclx

[tbase]

Just saw I posted on G4+ instead of G4X, sorry @Adamw

[Adamw]

Are you sure it is related to AC?  

In the pic below where my yellow cursor is, the AC clutch is off but lambda is 1.5 at idle. 

Just to the left of that at about 9:09 the AC Clutch is on and lambda is still about 1.5.

 

There are a whole lot of settings I dont like with your idle control though.  

[tbase]

Yeah, nothing else that I did, it's when I turn on car A/C control that wired to DI2 but I didn't check the A/C clutch status. 

 

2 hours ago, Adamw said:

There are a whole lot of settings I dont like with your idle control though.

Idle is holding ok for now but if you can give advice would be much appreciated.

[Adamw]

APS needs to be calibrated, it is only going as low as 1.5% so idle control isnt activating most of the time.  

E-throttle target table should have zeros right across the top row.

Change Idle actuator integral gain to 0.03.

The idle base position table needs about 2 added to it right across. 

Drop idle ign target to 10deg, increase idle ign max clamp to 30deg.  

Fuel system type should be set to MAP referenced or FP sensor if you had one.

 

 

 

 

[tbase]

Thanks @Adamw its work perfect now. 

[shanky]

On 11/30/2022 at 11:22 AM, Adamw said:

APS needs to be calibrated, it is only going as low as 1.5% so idle control isnt activating most of the time.  

E-throttle target table should have zeros right across the top row.

Change Idle actuator integral gain to 0.03.

The idle base position table needs about 2 added to it right across. 

Drop idle ign target to 10deg, increase idle ign max clamp to 30deg.  

Fuel system type should be set to MAP referenced or FP sensor if you had one.

 

 

 

 

Hey Adam, what was the reason you advised “Change Idle actuator integral gain to 0.03.” ? For my own learning / knowledge. Many thanks

[Adamw]

Mostly from experience.  Integral gain for E-throttle idle actuator usually works out around 0.02-0.05, Solenoid or stepper motor idle valves usually around 0.3-0.5.

Say if our idle RPM was 100RPM below target, for an E-throttle you may only need to increase the idle position (TPS in this case) by say 0.2% to reach target, in contrast with a solenoid valve you may need to trim the idle position (duty cycle in this case) by say 20% to bring the idle up 100RPM.  

If your integral is too high then you will see the actuator constantly over correct - usually observed as an oscillation but sometimes the min and max clamp can make it less obvious.  

A snip from the log above to give an example.  Where the yellow cursor is the RPM is only 150RPM below target, yet the ecu opens the throttle an extra 2.5% (idle postion runtime). So the RPM then overshoots, ecu closes throttle, RPM under shoots, ecu opens the throttle too much again, RPM overshoots...