(pictures below)
I've recently purchased a 2003 Disco II SE, though I'm having issues that I'm hoping internet people can help me resolve. My Disco is idling rough, vibrates at slow speeds, and cannot be driven more than 30 miles, or else it will sound like it's going to die. Per the advice of the forum, I purchased a quality OBD II scanner and pulled the following data (pictured below) off of the computer.

I've gotten a few different codes after clearing the computer and driving it to see what new codes appear, all of which are related to o2 sensors, rich fuel mixtures, and misfiring. The code that reappears the most, P0130 (02 sensor circuit bank 1 sensor 1), confuses me as the 02 sensors were replaced just before I bought the vehicle, and they were quality Walker Products 02's purchased from Atlantic British. I'm not sure if the o2 is what's causing the issues, here's what I've checked so far:
- vacuum leaks (no leaks)
- exhaust leaks (no leaks)
- fuses (no blown fuses)
- MAF sensor is new as well, cleaned it just to be sure
I'd imagine the next step would be to replace the 02 sensors again but I'd like to make sure before I buy them.

As for the 02 sensor/fuel trim data , I don't really know what I'm looking at but the data seems abnormal to me.
Engine codes:
P0130 (02 bank 1 sensor 1), (p0172 p0175 system too rick bank1&2)
Live data:
long and short term fuel trim banks 1 and 2 are around -20% - (-25%)
* 02 bank 1 sensor 2 and bank 2 sensor 2 display N/A for fuel trim data
02 bank 1 sensor 1 fuel trim: (-7.8%) - (4.7%)
02 bank 2 sensor 1 fuel trim: (-3.9%) - (3.1%)
(pictures below)

Other Questions:
* Pictured below, I found two hoses (one on coolant tank, one in front of drivers wheel) that are cut off and I was wondering if they're supposed to be like that.
* Also, near the driver's side downstream 02 sensor I saw what appears to be two cord-things you can plug something into dangling from a black cord. Anyone who can help me figure out if those cord things are supposed to plug in somewhere and if those hoses are supposed to be cut I would appreciate it.

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Any suggestions as to how I can get the disco running properly would be greatly appreciated, as well as any other helpful information. If there are any questions I'll answer them as soon as possible.
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obdII data:
Engine codes: P0130 (02 bank 1 sensor 1), (p0172 p0175 system too rick bank1&2)
long and short term fuel trim banks 1 and 2 are around -20% - (-25%)
* 02 bank 1 sensor 2 and bank 2 sensor 2 display N/A for fuel trim data
02 bank 1 sensor 1 fuel trim: (-7.8%) - (4.7%)
02 bank 2 sensor 1 fuel trim: (-3.9%) - (3.1%)



two black cords dangling underneath driver's side down o2 sensor, follow the grey line from the o2 sensor upwards to find cord endings I'm asking about. What are these? Should they be connected somewhere?

cut hose on coolant tank(highlighted), is this normal ?

Cut hose in front of driver's seat (highlighted), is this normal?

 

The cut hose off the coolant tank is an overflow hose. Normal.
Same with the cut hose on the firewall. Front axle/trans/diff (not sure which but its normal).

I’m prob not best to diagnose with these codes/data but I wonder if your plug wires/coils could be shot. Happens on these trucks and causes all sorts of arcing/misfiring.

 

The two dangling black connectors are for a transmission temperature sensor, if fitted. Ignore them.

 

I struggled with P0130 last fall and also have a BlueDriver. (P0130 is voltage issue with the drivers front O2 sensor)

I'd suggest looking at the front O2 sensors first.

Uncheck the fuel trim option and just look at the front O2 sensors voltage.

Attached are screen shots of mine with then engine running fine so you can compare so help see where your issue may be.

 

My father-in law-gave me four new knock off O2 sensors...easy to change out so why not. Drove f10 miles and stumbled died. Waited a few minutes and limped it home. I put the old ones in and ran perfect.

Start with the O2 sensors and their connections. Oil leaking from the valve cover gaskets like to drip right unto them.

The two wires by the transfer case are for the center diff lock. I have a 2003 and a 2004 with the diff lock...2003 just hanging in breeze.

 

The cut hose you're referring to on the driver's side is the breather hose for the front differential. Very important, haha. And normal.

 

Just a thought, but are you sure they are new Walker O2's? I ask because most Walkers I have seen have a black wire casing, not grey. The Bosch (OEM) have a grey wire casing. Just throwing that out there as something to look at.

 

Ah thanks for clearing up the hose things. The plug wires were recently replaced and are brand new, however, I have no record of ignition coils being replaced. Something new to look at, thanks for the help.

 

Thanks for clearing up the black dangly wires, makes sense now.

The 02 sensors are all grey, and the old ones are black. I have both a Bosch box and two small Walkerproducts boxes, so it appears the sensors that are currently on my Disco are Bosch then. Are Bosch sensors more prone to failure or something?

As for the o2 sensor voltage, all of them appeared to be similar to yours (keninnc), does that mean they're working properly by chance? The (bank 2 sensor 2) and (bank 1 sensor 2) fuel trims still display as N/A, and I don't know what that means or why it does that. All 02 sensor connections appear to be on properly. I'm not sure what the next step I take should be- should I replace the 02s, or look more into other potential issues? In the meantime, I've ordered an 02 sensor socket so that I can at least remove the sensors if need be.

 

Normally I'd suggest resetting the Adaptive settings after anything new like a MAF, O2 sensors, a basic tune up, fuel related work, due to the system learns over time and with worn out bits slapping in new ones = still set to old learnt settings. Needs to be reset to factory specs and then it can learn from there.