How do I test Mass Airflow Sensor (MAS) Engine 104.992 (3.2L)

I have a 1993 300E 3.2 with a 104.992 engine that recently started acting up on me. The "Check Engine" light is NOT on but when I start the car cold, it starts and idles fine but after about a minute or 2
the idle races and oscilates between 500-1500 RPM cycling in 1 second intervals then the idle becomes rough and the engine eventually stalls after 5 seconds of rough idle. Then when I restart the engine, I get a rough idle then it stalls immediately. Now, just recently, the engine does not even stay on for more than 2 seconds. When I start the car, it idles rough for a second or so then stalls immediately.
Here is what I have done to try and correct or diagnose the problem so far:
1. checked fuel pump relay w/jumpers (no diff) 2. fuel pump noise is audible when ignition is turned on 3. checked spark plug (strong spark detected during crank) 4. replaced OVP $70.00 (did not solve the problem) 5. visually inspected vacumm hoses within engine compartment (all's fine) 6. cleaned throttle body w/ carb cleaner
I would like to test the MAS unit to see if it is defective based on a suggestion from T.J. out of my original post but have no experience in this area. Does anyone have a simple method to test the MAS functionality in this engine? I appreciate any feedback. Thanks in advance.

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