Timing and Metering Valves

[TerryB]

When you say leaky injector do you mean it's not sealing off tight and letting compression back in? Or fuel leaking by internally in the injector allowing the timing to be incorrect? I know how to test for compression leaking back with the hose in the cup looking for air, I'm not sure how to test an injector for timing to see if the liquid cylinder is holding tight.