speed and reference sensor '87 5ktq - test?

[Ben Swann]

Patient: '87 5000 Turbo Quattro
Symptom: hesitation at high load, boost and RPM

I am following upon a check engine light 2111 code pulled which corresponds
to the RPM/speed sensor.

I have also been having a symptom of hesitation at higher load and RPM(3k
on up).

I installed new plugs cap and rotor which helped, but there is still some
hesitation at 1.3 bar on up to 1.7bar - yes the car has a mod.  This
symptom has been present on the car since I purchased it 10 months ago, and
I'd like to get rid of it, even though the engine otherwise runs fine.

I pulled out the reference and speed sensor assembly to clean, and there
appears to be some physical damage - particularly the speed sensor is
dented, and you can turn the sensor with respect ot its connector.

So although I will likely get a replacement, can I check to see if these
are still good even though they appear damaged?  There was a bit of crud to
clean, and some metal filings held onto both sensors magnetically which I
 suspect could have contributed to faulty operation.

Ben