Closed Loop State Disabled

[RGAClarke]

I have an M130 #5552 with GPA 01.07.0003, February 2016 Firmware receiving inputs from 2 LTCs.
The two lambda readings are visible and look OK but closed loop state is permanently disabled and the problem has eluded an authorised agent/tuner who spent some time seeking a solution.
Support suggested a Firmware upgrade to July 2019 but I note that only the GPR version is listed.
I now recall that I briefly operated the engine with IAT and Airbox MAF sensors disconnected and I wonder if this has led to closed loop state being disabled and if there is a simpler reset option ?
I also am aware that the Airbox MAF values are much lower than anticipated.

[RGAClarke]

Disregard Airbox MAF query. Change to translation table forgotten.

[David Ferguson]

Hard to guess without a package to look at.

Has this ever worked? Or are you trying to configure it to work for the first time?

Since you say you have two LTCs, I assume you have Lambda Bank configured. Is Lambda Single (Exhaust Lambda Collector CAN Bus) set to Not in Use? What is LTC Engine Run Time?

For Closed Loop, are all of the Thresholds and Activate values met?

What does Fuel Closed Loop Diagnostic show?

[RGAClarke]

Hi Daavid
Closed loop worked fine before running with IAT disconnected. (ECU default value was 20 C but actual would have been closer to 10.)
Yes running two banks and single bank collector configured to not in use. LTC engine run time is 10s.
As far as I can make out the thresholds and activate values for closed loop are all OK. Ditto authorised distributor/tuner.
Fuel Closed Loop Control Bank 1 & 2 Diagnostics are showing OK.
Thanks for your help.
Rupert

[RGAClarke]

Hi again David
Sorry about the spelling last time.
If it would help I could PM you my current Package and a smallish log file.
I would also be happy to pay for your time.
Rupert

[David Ferguson]

Rupert,

Feel free to email me directly - ferg@veracitydata.com.

[RGAClarke]

Another possible cause for closed loop to disable.
This does not explain why closed loop is disabled at lower power but I believe that the intake cam control is faulty.
Subaru SOHC Forester engines circa 2009 have a two position cam for one of the intake valves (AVLS) which is activated by solenoids on each bank at moderate speed/load.
My M130 is configured to use Inlet Manifold Flap Actuator to provide the signal to trigger these solenoids. This worked fine with a previous engine.
I am seeing low and erratic VE values from Quick Lambda at high power settings plus the calculated Inlet Manifold Flow value is lower than expected.
As an example the VE value from the previous engine at 5,500 RPM 95 kpa was 102.9. Yesterday at a similar point it was 97.7 and today 90.9. Calculated MAF was 123 gm/sec when it should have been 147.
Investigation required but any observations welcome.

[RGAClarke]

Solution.
Closed Loop Control State is disabled when Post Start enrichments are active.
In order for Post Start trims to be inactive the last "time in seconds column" of the table needs to filled with 0s.
This is entirely logical when you think about how the values would otherwise decay (presumably over an infinite time) but did not register with me.
It would be visible from the Diagnostic window for Fuel Volume Trims which would show Post Start Trims still adding fuel long after the last "time" setting in the table had passed.
Thanks to Stephen for taking the time to sort this out.