NOTE: These are my notes from a generic fuel injection book.  Readings are approximate.  I have not done these procedures, but they sound reasonable to me.  Corrections and updates would be appreciated.

bulletAt pin ? (sorry, I don't know which one!) of AMM, check for roughly 2 volts at idle, increasing to roughly 2.75 volts at 3000 RPM
bulletNo change?  Bad AMM

 

bulletVisual inspection
bulletRemove the Air Mass Meter
bulletLook through the screens to see if you can see the wire.  It is supposedly extremely difficult to see the wire, so look hard.  Is it there?  Does it appear to be intact?
bulletEven if the wire is intact, the AMM electronics could be bad.