Verify the MAF is unplugged and the connector isn't shorted out. Do the same with the extra MAP plug (Factory and extra one on adaptor harness by ecu). Make sure you have a 3 bar sensor and not a 1 bar. Your post says a FAST B2B but your signature says XFI. If it's an XFI, go to View/System Config/Sensor Calibration/MAP sensor and verify the RAW MAP voltage and the MAP calibration are correct.