I have a 2000 4.3l v6 2wd. Between 1,700 and 2,000 rpm the engine seems to miss/sputter. Only if I accelerate slow or moderate. If I accelerate hard it's at least not noticable. It's always at this same rpm range. And I've only noticed it when it's raining. Didn't do it when it was cold and snowing. Otherwise it seems to run fine.
Thanks.

Probably needs a new distributor cap. Supposedly condensation falls from an A/C line on the cap and shorts them. Supposedly you can get a sleeve put on the line to help, probably just more insulation

Check your sparkplug wires and boots too. Had an Astro van with the 4.3 that did the same thing. Replaced the wires and problem was solved.