How do I tell if 5 weak injectors or a weak pump?

My car seems to run a little shakey at idle with a slight miss on some of the cylinders. If I turn the idle up to 1000 RPM's it's smooth as a top. My guess is it's not spraying a good strong mist at a low RPM. Weak ip or injectors?

I pulled the number one Injector out of the head and put the line back on and started the car and didn't notice any spray out of it but it was right next to the hole it goes in (number one pre-chamber) and the breeze coming out of that cylinder may have made it hard to see the injection spray. Is there a good way to test the injectors. No shop within 45 minutes or so.

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