Before we first started the car we noticed that the SAFC was registering Airflow.. But while driving around and playing with boost last night a little we noticed that it wasn't registering ANY airflow... we can still control the fuel etc... Any idea's?

Formally Project Solar Eclipse
Now Entering 300ZX Land.

Jim Wolf ECU w/ Boost Jets
Jim Wolf Pop Charger Intake
Eibach Pro-Kit Lowering Springs w/ Fully Adjustable Gas Shocks
B&B Exhaust - 3" w/ Dual 4.5 Oval Tips w/ 3" Test Pipes
Konig Five-O 17X8 Rims w/ Polished Lip
Blitz Turbo Timer /w Boost Gauge
Freshly Painted Calipers
Stillen Unorthodox Pulley
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Stillen Short Shifter
New RPS Clutch / Pressure Plate / Flywheel - Holds 550 ft lbs of Torque
New Fully-Built 5-Speed Transmission
New Howe Radiator w/ 18" Electric Fan w/ Auto Thermostat Controller
New Yokohama ES100 Tires All Around
New Tension Rods
New Fuel Injectors
New Spark Plugs
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New Vacuum Hoses
New Heater Core
New Fuel Filter
New Ignition Control Module
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You check all the wiring to make sure it didn't come loose and that you have the right airflow setting chosen on the AFC?

we followed the instructions on tuning the SAFC on the main page of 2gnt.com. We have the sensor set at 06in 06 out... I'm thinking it's a loose connection... very possible it came loose while installing the MSD..

How would that affect the car if it doesn't register any airflow on the SAFC?

Formally Project Solar Eclipse
Now Entering 300ZX Land.

Jim Wolf ECU w/ Boost Jets
Jim Wolf Pop Charger Intake
Eibach Pro-Kit Lowering Springs w/ Fully Adjustable Gas Shocks
B&B Exhaust - 3" w/ Dual 4.5 Oval Tips w/ 3" Test Pipes
Konig Five-O 17X8 Rims w/ Polished Lip
Blitz Turbo Timer /w Boost Gauge
Freshly Painted Calipers
Stillen Unorthodox Pulley
Stillen Front Nose / Bumper
Stillen Short Shifter
New RPS Clutch / Pressure Plate / Flywheel - Holds 550 ft lbs of Torque
New Fully-Built 5-Speed Transmission
New Howe Radiator w/ 18" Electric Fan w/ Auto Thermostat Controller
New Yokohama ES100 Tires All Around
New Tension Rods
New Fuel Injectors
New Spark Plugs
New Motor Mounts
New Vacuum Hoses
New Heater Core
New Fuel Filter
New Ignition Control Module
New Hicas (4-Wheel Steering) Lines
New Brake Pads / Brake Lines / Master Cylinder

I'm not sure how they are are setup on a 420a so I can't say I know on a 4G63 you splice that wire and it's what the ECU reads the adjustments on so there would be a problem tuning if it didn't register.