finnsmith

(1988 944, 94,XXX) just yesterday i started to hear an abnormal clicking coming from the top of the engine, around the cam housing and fuel rail. its more pronounced by cylinder 2. my injector on 2 is clicking a little louder than the rest, but it also appears that it could be a collapsed lifter as well. i have a stethoscope, but im not sure of the points that i should put it on the housing to diagnose the lifters properly. is there a good way to go about this or an easier way to diagnose it?

Zirconocene

If you're willing to let your engine run poorly for a little bit, you can pull the injector plug on cylinder 2 and see what changes. There's some risk there, though, if you disturb the wiring; it's all pretty crispy at this point and it's difficult to predict how the old wire sheathing will react.

If there's no change with the injector unplugged, I would suspect the lifter. I'd bet a nickel, though, that's it's the injector. Have you run some Techron through the fuel system? Alternatively, you can get your injectors sent off to be cleaned and flow balanced for relatively little $.

Good luck