Cylinder 2 Misfire and vacuum hoses look shot

2012 Pre Runner 2.7 bought new in 2012 now has over 296,000 miles on it. Vehicle bogged down yesterday and threw CEL light flashing, checked code and it came back Cylinder 2 misfire. I had played around with some of those splitfire plugs about 50K miles ago so first thing was replace them with OEM's, still getting misfire on cylinder 2, swapped out cylinder 1 for cylinder 2 coil and still throwing code for misfire cylinder 2. Buttoned her back up and added a full quart of LUCAS fuel system cleaner and ran down the road for about 30 minutes. Drastic difference in performance, still stumbling from time to time but hasn't thrown a code, thinking that it may be a fuel injector issue. No good at or to be more specific I'm totally ignorant as to testing anything electrically. Going to drive her today and see how it behaves, next move might be to have injectors cleaned with that concentrated crap hung like an IV bag. I did notice that my vacuum hoses are getting brittle and old, I would like to just get under the hood and replace all of those at one time, can I purchase a few rolls of this stuff and just go for it? What's a good source for bulk tubing specific sizes for this engine? I had seen a few years back a posting about the sizes for a swap out but when I do the search it goes google and takes me everywhere but where I want to be. Thanks guys, this forum has bailed me out more than once on maintenance that would have cost thousands.

*UPDATE* after almost 120 miles of driving with the LUCAS gas treatment, full bottle of the concentrate that 3 ounces will treat 10 gallons the stumbling has all but stopped, throttle response is and pick-up on hills noticeably better. Found clear tubing at ACE Hardware and may try to swap some of my brittle and aging vacuum hoses with that stuff.

 

You might have to order the hoses online. I'm in South Louisiana and all the autostores have been out of most bulk hoses for about a year.

Do you have a tractor supply near you. Mine had the tubing on rolls in an aisle, but i think i slowly bought most of it LoL, it gone now.

 

Going to Tractor Supply now, thanks for the tip.

 

I would call them first.
They don't all have the same inventory