Help with flashing CEL/Misfire's 5 & 2

Apologies for the long post, but I welcome any feedback, positive or negative. I know I've made some maintenance choices that may be catching up with me now.

Here’s the situation: 2004 Tacoma Double Cab, 3.4L Prerunner, 2WD, 220,000 miles.

Incident: While driving home, the check engine light (CEL) started flashing, followed by rough idling and partial loss of power. The truck vibrated heavily when trying to accelerate up to about 40 mph and shook when I let off the gas. I managed to limp it home, about a mile, and then shut it off.

Known issues before the incident: The valve cover gasket has been leaking for a while, but not enough to require adding oil between 5000-mile oil changes. I've been driving with a P0420 code (catalytic converter), but without symptoms of failure, I assumed it was the O2 sensor and kept driving for a few months.

The reason I hadn’t fixed the sensor is that I had previously JB-welded it back in place. Fixing it properly would require shop work. There were no exhaust leaks before or after the incident that I could find.

What I've done so far:

Checked for exhaust leaks.

Pulled codes, showing misfires in cylinders 5 and 2. Replaced spark plugs and coil wires (which needed replacement anyway, they were in rough shape). Everything smelled like gas, including the air filter, though there was no residue in the airbox.

Pulled codes again: same misfires in cylinders 5 and 2, still rough idling and flashing CEL.


After reading up, I'm thinking it could be faulty injectors, but before I spend more on parts, I'd like some advice. I'm working with basic tools and would need to rent equipment for any fuel pressure tests.

I handle most of my truck’s maintenance—belts, plugs, oil, brakes, ball joints, steering rack bushings, struts, etc.—but if this seems too complex for DIY, I’m open to taking it to a shop. Any input is appreciated, I just want to get my truck I've owned since 2009 back on the road!

Picture for attention, I'll upload relevant pictures later.

 

Cylinders 2 & 5 share the same coil... I would suspect that first. Transfer a coil from another cylinder to see if the miss follows the coil. Easiest thing first, and if it is a coil, factory only.