2015 L96 6.0, E38, installed in 1972 Blazer, MT

Have a persistent P0106 (MAP Sensor). Truck is running very well however, with no drivability issues.

Replaced the MAP sensor, validated MAP orientation in the intake, all wiring positions, etc.

Checked all conditions with a scanner while vehicle is driving down the road.

Only anomaly we found, was with the speed being reported at the OBD2 port, it is half of the actual vehicle speed.

We are supplying a VSS signal to the E38 from the mechanical speedo port on the xfer case, using a dakota digital SEN-01-128. We are pretty sure that the reduced pulse rate on the VSS signal we are generating, is due to to gearing of the speedometer output, at the Xfer case.

So, we will get a dakota SGI-100 and we will step up the pulses per mile, so that the VSS pulse rate (pulses per mile) is accurate.

But I don't know if this could actually be causing the P0106?

I have heard that on these later engines, the VSS is more actively used, to determine engine loading, and thus control the fueling, and could be causing the P0106, due to the E38 determining that the MAP is out of range, based on the vehicle speed which the ECM thinks is about half of actual speed...

Anyone ever run into this problem?