Fuel injector leak testing

[KCRN12]

What's the best way to check for leaking fuel injectors?

 

[mwolson]

Put a fuel pressure gauge on your fuel rail, turn the key on. The fuel pressure should go to 39 PSI. Turn the key off. If the fuel pressure stays at 39 PSI for at least several minutes, then you know the injectors are not leaking. If the fuel pressure leaks down quickly, then you may have one or more leaky injectors, a bad fuel pressure regulator or a bad check valve in the fuel pump.

 

[KCRN12]

I already know there's a leak. I know the regulator is working properly. I'm trying to differentiate between the check valve or injectors. So if I find out it's not the check valve, how do I isolate each injector to find the leak?

 

[mwolson]

The only way I know is to yank them and have them tested. Maybe you could pull the plugs, key on and see which cylinder gets fuel. Don't use a match to look.

But if the intake valves are closed...