is there a way to check fuel injector to make sure they are working.
You could get a automotive stethoscope and lister on it clicking while it is running. It will sound like a bee buzz.
On some cars you could easily pop them out but leave them hooked up to see if they spray into a cup. On others they have to be removed from the vehicle.
@dripper if you want to be REAL cheap, use a long flat tip screwdriver. Place the tip on the injector body and the handle on your ear. If you hear clicking, they’re opening and closing. This will, of course, NOT tell you if they’re partially plugged or dripping after engine shutdown.
If you listen to all of them with either method, the one with the odd clicking is a likely suspect. Also, a visual spark plug reading can tell you if that cylinder is firing normally.