Stuttering During Acceleration

I've been trying to help a friend get his 2000 V6 Tacoma running right lately, and looking for some ideas on what to check next.

It recently also had a rough idle and he replaced the TPS and it solved that (idles very smooth at 750 rpm). We checked resistance on all 3 coil packs and all 3 tested at 1.1 ohms. We cleaned the MAF. He says he did plugs and wires a couple years back (they visually appear OK).

Any possibility he screwed up the install on the TPS?

The truck sits a fair bit (not a daily driver) next to wood pile and the rodents have been around, as there's droppings all over the engine bay. Everything else works (electronics wise) and there's no obviously chewed wires. Any ideas on what to check and rule out next. Oddly the truck stutters if he gives it throttle around 2k rpm in 3rd gear. Same speed he drops into 2nd gear and it revs out very smooth. Stutter only seems to happen between 2-3k rpm (very smooth at lower or higher RPM).

 

Have you tried fresh gas?

 

No but I don't think it's that. The whole cluster of symptoms came on suddenly as he was driving it up to a camping trip. He does drive the truck at least a couple times a month. But we can definitely try that. It feels more like something electric or spark related

 

Need a scan tool. Maybe an injector is partially clogged or a weak coil pack. I've seen several idle ok but under load start to get weak.

 

Ok that makes sense. Only reason I didn't think it was fuel related was because it was only in that mid RPM range. You think a partially clogged injector could perform okay at high RPMs even if it's causing problems at 2-3k rpm?

 

Without pulling them out and checking the spray pattern it would be hard to tell. That would be one of the last things to check if all else fails. A scan tool would make diagnosing your issue a lot easier.