P0301 code and missing

I just got a bad miss and a P0301 code. The plugs should be good >3k miles on them. I'm guessing its a bad coil pack and I'm getting ready to swap that coils to see if the problem follows the coil location. How often do the coil packs fail?

 

I would try a couple of easy things first. Clean MAF sensor and dump some fuel injector cleaner in tank. Changing coil packs is alright but if that doesn't work I guess next thing would be to swap out fuel injectors.
How many miles on your Taco?
Even if you just put plugs in one of them could be bad. Happened to me, ended up throwing a brand new plug away.
Well just giving you a few things to look at. Good luck!

 

100k+ , I swapped the #1 coil pack for the #4 (easy to get to) and it's now throwing P0304 code ...So I think I've found my problem.

 

Great! Their around 60 bucks at Rock Auto, no idea what the Toyota dealer will want.

 

$80.00 at Advance auto but it's Sunday and that's the price you pay to have all 4 cylinders firing. It did fix the problem. Thanks


Any idea how common that failure is?

 

I've only had one go, and I'm pushing 225k miles.

 

10-4, I'm trying to decide if I want to obtain a spare or just take my chances with the 3 older coils.

 

Just take your chances. If anything buy an oem and keep aftermarket as spare.