Help Needed With Closed Loop Fuel Control / Closed Loop Mode VS. Airflow Table

[Jason H]

Hello,

I'm trying to help a friend out with his LS swapped 2006 Trailblazer SS. I spent some time going about tuning the VE table correctly using an AEM wide band UEGO gauge. Getting this done was pretty elementary and the truck runs great in open loop mode. I have errored out the MAF and addressed the fault codes so it functions as a speed density system now.

When I reenable closed loop it begins to build a large positive trim on one bank and a large negative trim on the other bank. Which bank goes positive and which goes negative will change based on coolant temperature it seems.

Under Engine - Fuel - Oxygen Sensors - Feedback - Airflow - Mode VS. Airflow there is a table that I cannot clearly understand. I'm not exactly sure what it does and I'm not exactly certain what parameters to log for this or how to properly tune this table. I believe that this table helps scale the narrow band oxygen sensors to match the wide band sensor that was used to tune the VE table but couldn't say for sure. If anyone has information on this that they could share I'd really appreciate it.

Thanks in advance.

[RobZL1]

The mode vs airflow simply defines "buckets" for ranges of airflow, and these buckets are used to define other tables on the page (e.g., "if the airflow is in bucket X, the proportional coefficient = Y").

If you've got large trim discrepancies between banks when you re-enable closed loop, you've got something else going on (possibly swapped O2 sensors bank-to-bank).

[Jason H]

The mode vs airflow simply defines "buckets" for ranges of airflow, and these buckets are used to define other tables on the page (e.g., "if the airflow is in bucket X, the proportional coefficient = Y").

If you've got large trim discrepancies between banks when you re-enable closed loop, you've got something else going on (possibly swapped O2 sensors bank-to-bank).

I have verified that the oxygen sensors are installed in the correct banks. I have also verified that there are no mechanical issues with either bank that would lead to this. As I said above the issue will swap from bank to bank depending on what the engine temperature is when you start the vehicle.

Do you happen to know what channels I can monitor to identify which on the table it is operating in at a given time?