Hi all, Removed the fuel injectors to clean them on a RS K100 1986 due to stale fuel in the tank. 
Measured the ohms on them, 3 of them read 16.plus, 1 read 7.7 This one is pictured with the dis-colouration.

   
Does the dis-colouration indicate anything? 
Is the injector dead or professionally fixable? When activated the 'click' is not as clear as the other 3.
If its better to obtain another, any suggestions [has anyone tried others with success]?  
The numbers on them are 552 on the connector, 0 280 150 210 on the body
Cheers  Dale

replace the low resistance one with the same type
im sure someone here has a spare around the place somewhere

id be guessing that there is some issues inside the injector itself

Looks like the steel body of the injector has left a rusty stain on the alloy.

It also turns out like that when you have a small leak at the o-ring.

If you can't find a #210 and need to replace the set with a different type, as far as I can determine the 0280150705 is the closest match which is the injector for the 16v

What you're looking for is...
Single hole pintle
Impedance around 16ohm
Operating pressure of 2.5 bar (36psi)
Flow rate of around 160 to 165 cc/min at a test pressure of 3.0 bar (43psi)

Thanks for the comments, its given me a direction to go. Dale

Hi Dale, I can send you up a couple of Blakeys refurbished ones to try out. Give me a PM, my daughter is coming tomorrow and lives at Warrimoo so I can get them up there by tomorrow night.
RT