IIRC, you should see one skipped cycle... (working from an old mans memory
here and my manuals aren't close to hand). I would think that there should
be a "signature" that the PCM can count from to determine position so expect
to see one drawn out wave amongst the rest. Most common problems are an open
or short.... a short would deliver lower than expected amplitude (depending
on the nature of the short) right down to a flat line. An open would also
give a flat line (but I'm sure you know this since you have a scope....
threw it in for the less knowledgeable). I'd also look to see if the signal
was dirty... RFI can play havoc with these sensors (hence the twisted pair
Fords test procedure doesn't include using a scope on the sensor. Be aware
that it is possible (if the connector hardshell has been apart or replaced)
to hook these sensors up backwards. AFAIK, there is no way to be to check
for this electronically... if you need, I'll try and remember to bring my
laptop home (it has the manuals on the HDD) when I'm uptown later and we can
check colour/pin assignments.