Need Expert Opinion - Lean in boost

2009 G5 powertrain. Supercharged and tuned on HP tuners. 2.9 pulley, dual pass, 42 lb injectors.

Runs great in MAF only mode
Runs great in VE/dynamic air only mode

When running in closed loop with dynamic air and MAF on, it runs great until about 5 PSI then skews lean

I had to build the VVE table by hand above 105 KPA because it ends there stock. It's not perfect, but it's decent and runs well.

I can't find anything causing the lean condition. It has to be a coefficient or something referencing MAP that didn't get built out for boost, but I can't find it.
All input welcome.

Attachment 121979
Attachment 121980

Did you tune the MAF all the way up to redline or stop before PE? I found that when I upgraded my airflow I exceeded my MAF and it goes lean at 12,000 Hz no mater what mode i'm in when the MAF is enabled. Another thing that happened to me was that I exceeded my VVE table which caused it to go rich. I had to use the drop down to change it over to a 3 bar model and change the hysto to match the larger map. Just a couple ideas.

the maf ert tests arnt right may be affecting its use set to stock see if it helps

Thanks for the responses. Much appreciated.
I checked MAF ERT tests vs stock and they are all the same. My motor was equipped with SAI, so it could be different than other models.

I'll confirm MAF and VVE tuning again this weekend. I'll be sure to really wring it out. I haven't seen above 10,000 HZ on my MAF and the scale goes to 15,000. My VVE didn't have a drop-down, so I extended out the labels to build the table. I re-zoned the table so all zones were equal.

Quote:

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Originally Posted by 07GTS

the maf ert tests arnt right may be affecting its use set to stock see if it helps

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I think you're onto something though. If it's not failing, it could mess with the VE tune. I set it to 20 seconds to see if that changes anything. Should have data tomorrow. Thanks!

how did you disable the MAF?
If you just unplugged it you can't do that without rewiring in another IAT circuit back through the MAF harness. The built in IAT on the 5 wire MAF has a huge impact on VE tuning; particularly when under boost due to heat of compression.

Typical 5 Wire MAF Pinout
Attachment 122183

those maf ert test MIN are usually set to 1 sec, test IGNV min is 10v

I relocated my IAT to a 2.5 bar TMAP on the supercharger maifold. I was disabling it by setting the maximum hz to 100. I think the timer was preventing it from actually faulting though.

So if you click the row header on the left of the map in the VVE or SD calibration it will give you an option to change it to 1, 2, or 3 bar. It May be MAP or Pressure Ratio depending on your ecu I think. I'm just a beginner so I'm not sure what your ecu looks like in HP tuners, but im pretty sure that can be changed to accommodate calibration higher than 105 KPA. with your supercharger you will definately need it.

Well you avoided my rookie mistake from a few years ago. Thats good. ERT is usually well below the start threshold. 07GTS is right, should be 1s, above 300-400 rpm with a 8V or higher IGNV. I wouldn't set it much higher than 10V as mentioned though. Not really any good reason to run the IGNV up high unless you dont want the test to trigger for some reason.