Do you mean fuel isn't getting to the 5th injector, thus it being dry? Delivery valve issue I suppose, maybe the DV is leaking....but it'd have to be leaking BAD for it to kill the injector.

Or do you mean there is fuel literally on the 4th injector? I don't know what to make of your picture to be honest.

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1998 Ford Escort ZX2 5 speed - 279,000 miles My Daily

1992 Mercedes 300D 2.5 202,000 - Pure junk
2000 Mercedes E320 Black - 136,000 miles - Needs repair

Don't forget to grease the screw and threads on the spring compressor.