Diagnosing idling issue

[Wally1552]

First off apologies if this isn't the right place but I didn't see a section for ISTA diagnostic type discussions.

Long story short I'm currently troubleshooting a few fault codes related to idle and limp mode issue. Car has a minor erratic idle at stand still. It died once during applying light throttle. Will go into limp mode about a few miles after clearing codes.

Finally got fed up with Carly app and was able to get ISTA+ up and running on my PC. I'm very much not an IT or computer expert so bear with me. Please see ISTA screenshot below.

Car: 2011.75 E90 ZCP

Fault codes:
1) 002B23 - idle actuators controlling monitor bank 1
2) 005E19 - DSC engine management interface
3) 00278D - BSD to DME alternator missing


Background:
- Car has 95K miles.
- Stock tune right now (used to have Alpine stg 1 and DCT)
- ICV almost new. Less than 12K miles. Bought in May '20 however it failed ISTA function tests (now replaced by my old ICV)
- new ICV tube (connects the plenum)
- TA's One is brand new (bank 1) the other has about 30K miles on it. Both passed function tests
- New Fuel breather valve
- new precat O2 sensors both banks
- Map sensor is original
- Indie shop informed me my plenum was barely on correctly and maybe part of the issue. It's been reseated properly now.

ISTA Screenshot:
I ran a function test of the ICV and it returned the below results. Does anyone know if this means my ICV is definitely not working?

View post on imgur.com

I also tried to run some throttle actuator tests but they are grayed out and cannot run tests. Anybody know why?

View post on imgur.com

[Wally1552]

Update:
Received my new ICV came in today and I feel pretty proud I was able to swap out from jacking the car to putting back air filter in about one hour! First time I did this DIY it took me about 4 hrs start to finish.

Ran ISTA tests on the new ICV. Everything passed except integral ramp 2 error but I believe that means nothing. So first ICV failed ramp 1 and 2. Second ICV failed only ramp 2 which indie recommended I replace and now this 3rd new ICV also failed ramp 2. Is this even a real error?? I'm going to now road test it for next couple of days to see if any idle errors come back.

I tested as many sensors related to idle I could think of including intake air temp sensor, intake vacuum pressure sensor, O2 sensors and all seems OK.

I will keep this thread updated.

[woody888]

When you read out the info from ISTA ICV test, was that anything wrong on the ICV? any symptom?

[Wally1552]

Originally Posted by woody888

When you read out the info from ISTA ICV test, was that anything wrong on the ICV? any symptom?

The ICV that was in the car at the time of limp mode failed integral duty ramp 2. The symptoms was check Engine light and then limp mode. Both cold and warm idle would fluctuate between 500 to 1000 rpm but cold idle was worse than warm idle. One time at a light it stalled out. I replaced ICV with a brand new unit but even that failed ramp 2 test but it has been about 2K miles with no idle issue at all.