2005 5.4 3V - multiple codes
 

2005 Navi, running like el crapo with CEL. Codes:

P0300
P0305
P0306
P0307
P0308

Misfires on all bank 2 cylinders. Also throwing P2198 O2 sensor and P0175 rich on bank #2.

So, where do I start? Replace the O2 sensor, since that seems to be common part?

I would start by correcting the miss fires 1st. start with fresh plugs and check the COPs...make sure everything is firing correctly. then I check the injectors....Ford did a extended warranty/customer satisfaction on them for 05', maybe your Navi will qualify?

I have a hard time believing all of the plugs and/or COPS decided to crap out on the same day. The truck was running fine on day 1, on day 2 it took a crap and started throwing all the codes.

How many miles are on your truck? Did you drive through a bunch of water? or wash the engine bay?

Its hard to say what happened in what sequence of events? To get a better understanding of whats happening you will need a scanner capable of a "mode 6" scan...meaning it is able look at exactly how the sensors are functioning and the rate of misfires, ect. but that isn't cheep

The misfire codes showing all four cylinders on the left/drivers side strongly suggests the wiring harness connector for that bank leading into the larger harness connected to the ECM has become an issue. I'd check that first.

The 02 sensor might be throwing a code since too much unburned fuel is being pushed into the exhaust stream due those misfires.

HTH

Where do I find this widget? Is it replaceable? This truck is fairly new to me, so I'm not sure where all the bits and pieces are located...

Also, no water, just driving down the freeway and it started bucking and running like crap, no power, then throwing codes.

Without offense to you it might be time to bring in the experts with the shop, tools and whatever else needed to diagnose and repair this in a more timely manner.

Not being made of cubic dollars, that is not an option. If I had the resources to spend on a dealership "hide and pay" mission, I would not be here.