i tried spraying the carb cleaner on my instake manifold and it didn't do much. it did, however, make a small popping noise when i sprayed it on the gasket at cylinder 3 (the cylinder that I replace the ignition coil on). i don't know if this is due to the heat of the engine or a leak in the gasket.
i'm still going to go through w/ replacing the fuel filter, replacing the PCV valve, and maybe trying some Lucas fuel system/injector cleaner this afternoon to see if that makes a difference.
but, after hearing that popping noise, i'm leaning more towards a leaking intake manifold gasket as the main problem.
for those of you who have replaced their gaskets, how long should it take and do i need anything more than a ratchet, screwdriver, a new gasket, and gasket sealant? i've read the instructions on the isuzu faq, but i want to hear first hand how much a of pain in the a$$ it is before i give it a go.