i think i have a bad injector. how can i make sure of it? I know how to do the resistance test, ive swapped plugs with another injector. and this is the only cylinder (#3) where i can unplug it and feel no difference. i left it unplugged and rev'ed it and it sounded the same as always. have i done enough justifcation to say its bad? or is thier any more tests i can do? also. thesea re the ford svo's. can i purchase those seperately? i look at summit breifly but seems i can only get them in packs of 4.

 

You could try pressurizing the line with your FP gauge hooked up.

Unplug that injector

Momentarily fire the injector from an external +12 and -ground source (wired from the battery will work) and see if the FP gauge drops pressure when you do so.

There are balance tester kits, run about 50 bucks or so, that does the same thing and are more accurate, but for just a quick test on one injector to see if it's clogged or working, you can do as I mentioned above.

Unsure about buying one or not.