How do you check for a leaky injector?

[John B]

My fuel rail doesn't stay pressurized (after I turn the engine off for a while)and I can't find an external leak. How can I determine if an injector is leaking?

[5sp. mini]

i heard that you remove them with the fuel rail hooked up and turn on the key to presser up the inj. and see if they leak. AL

[shadow88]

You could crimp off the fuel feed and reutrn line with vise- grips with a fuel gague hooed up. If the fuel pressure drops then you know it's an injector. Or if the pressure doesn't drop, remove 1 vise grip at a time. If the pressure drops when the feed side vise grip is removed, it's likely a bad fuel pump check valve.
If the pressure drops when the return side vise grip is removed, it's likely a bad fpr.
If the pressure drops with both vise grips attached, unbolt the fuel rail, put some dry rags under each injector tip and see which one(s) are leaking.

["Top Fuel" Bender]

If the engine doesn't run rough when first starting
(from the extra fuel)
I'd lean more torward a leaky check valve at the pump
Nothing really to worry about though
most cars loose fuel pressure