Lazy upstream O2 sensor - concerns? (w/ screencap)

Reprise

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Happy to report that I've finally got my short- and long-term fuel trim issues resolved. But my upstream bank 1 sensor is still 'lazy' - here's a Torque screencap (oh, and the upward spike on the left is from me raising the RPM a bit to observe voltage changes):

1575502809573.png

Metrics (after 75-100mi and a few drive cycles): (6.0L LQ4, 235K)
- STFT ranges from 0% to -7%, usually in the negative 3-ish range.
- LTFT is 0% (dunno how long that'll last, but for now, that's as good as it gets)
- No codes whatsoever (lit or pending)

- Oil control and coolant levels are solid on this engine (so no fear of sensor contamination)
(I did note a little oil surrounding the gasket / intake ports when I removed the intake again; apparently, that's from the PCV system, and gives reason to put a catch can in... which I'll do in the spring)

- Slight ignition miss I had before repairs is now gone. Engine runs beautifully, great oil pressure, etc.

Question: Would you be in a rush to replace the two primary O2 sensors, if you were planning to leave for a long (3500 mi / 3mo) trip with the truck, towing about 6000 lbs?) Trying to get out of here before the snow starts falling (although I'm waiting for my SoS to send my renewed D/L in the mail, so I can't leave 'today', anyway).

I know if I touch the sensors, I'll run into issues (because I always have 'issues', when I repair something.) Like breaking off the sensor in the threaded bung. Or not being able to remove it. Those kind of 'issues'.

Info I have is that if things are running as well as they are, it shouldn't be too much of a concern. But I know if the B1 sensor goes, my cat on that side is at risk (and I'll be far from home)

As far as how long this B1 sensor has been 'lazy'... probably since I've had the truck (about a year now)
 

Mooseman

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Dec 4, 2011
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Ottawa, ON
With those fuel trims, I'd wait to change them. At worse, it will die but it'll still run and you can get it done at a shop at your destination (easy job for them). Or have it done at a shop now. Should be an hour job, tops.
 

Reprise

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Thx for the input. I did think about it dying mid-trip -- but now that I think about it some more, it's not like I won't be already be running Torque to keep an eye on things during the trip, anyway.

I'd bite the bullet and have it done if on the road... but here at home, even though I like to b!tch about how long / how much effort things take me to do, I prefer to do them, if I'm capable.

When I had the new muffler / tailpipe welded on a couple of weeks ago, I felt like I got taken (long story, but the job got done, for about $100 more than I thought 'fair'). At least it's quieter now.

When I took the truck in today (different place) to have the used tire I bought mounted on the spare rim, I felt like I got taken, again (they refused to mount either of them, saying 'the bead was ripped' on both, and they were 'basically junk'... and me not wanting to run from tire shop to tire shop, I wound up buying a new one to use as a spare... burned the hell outta me.) :mad:
Again, job got done, but another $100 or so spent for a new tire that'll probably never come off the winch, except to lube the cable.

Yeah, I've got trust issues... lol... BIG ones... :laugh:
At least they didn't try and tell me the rim was bent (I had to source one of those, too, since previous owner had the big-ass 315s from an H2 on it (and no spare)). :Banghead:
 
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Mooseman

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Dec 4, 2011
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Ottawa, ON
You need a DIY Garage like I have here. It's fantastic with tire machine and balancer available. I'm buying a set of 19" tires for the Caprice for $100 that are excellent except one has some outer scrub wear. Any tire shop would just sell you a replacement for that one but I'll just put it on the back and wear it evenly :biggrin: . But yeah, I trust garages like I trust used car salesmen, dealers and politicians. I did find a shop nearby that seem to be straight shooters. Took my wife's beater for an alignment after replacing the tie-rods and they did not try to BS me with unneeded repairs. The rear adjustments are rusted solid but said it can be driven that way even with camber a little out of spec. But I digress...

Drive it till it dies, and if it does, git 'er done then. If I had the time, I would probably replace it.

Edit: Typo fix
 
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littleblazer

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Jul 6, 2014
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It should be a stainless sensor seat... I never had issues getting sensors out on that era truck. But I understand the want to wait. The chances of it dying are slim anyway and the extra heat from towing will probably wake it up some anyway. I think you're fine.
 

Sparky

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Dec 4, 2011
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If you want to be sure the sensor comes out, hit it with PB Blaster a few times over a few days before replacing if possible. The Blaster plus hest cycles will work on it and make it break free easier.
 

Reprise

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Yep - I had hit both primaries with the PB a few weeks back when I was getting real cozy & intimate with the steering box & P/S hoses, expecting that I'd be replacing them (I knew the sensors wouldn't 'get better', but one can hope, right?)

Thankfully, this truck hasn't succumbed to rust like the last one did, having spent 1/2 of its life in TX (I'll never buy another 'northern' truck again, as a result.)

Day is starting out well - just checked my SoS site as I write this, and FINALLY got a status of 'card mailed' ( new D/L). I may actually get to leave, after all! :woohoo:
 

mrrsm

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If it comes down to cases and the USO2S has to get 'Pulled like a Bad Tooth"... I'd like to suggest a Tool Combo that will compliment the ease of getting this PITA Job done... Glass Smooth. The Main Player is the "Dog Leg" Oxygen Sensor R&R Tool... along with one of the Hollow Tube Handles I cut off of a Pair of Dull Brush-Branch Nippers.

The OEM Brand O2 Sensor R&R Tool is available on Amazon for $23.00:


OEMBRAND02SENSORTOOL.jpg

Between the two of these... I've been able to carefully hold the Hex Head of the O2 Tool with my Left Hand very snugly over the Hex Base of the O2 Sensor to prevent it from slipping and stripping the surfaces ... while using the Extra Mechanical advantage the Hollow, Large Caliber Rubber Handle adds after telescoping it over the R&R Tool Handle. In every case... those O2 Sensors have Yielded and unwound without a problem. Here are some images of how these two items manage to work this Magic together:

O2SENSORTOOLS.jpgO2SENSORTOOLS1.jpgO2SENSORTOOLS2.jpgO2SENSORTOOLS3.jpg

If that technique (or anything like it) fails to budge the Damned Sensor... As per @Sparky 's PB Blaster suggestion...@MAY03LT echos using that Rust-Busting Spray Solvent and follows this interesting approach to solve the very same problem:

 
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Mooseman

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Dec 4, 2011
25,262
Ottawa, ON
I took a 22mm deep impact socket and cut a groove in it. A few times I have stripped the hex on sensors with traditional 7/8" sensor tools and sockets. 22mm is just a little tighter and impact socket doesn't flex at all compared to some sockets.

And I also recommend using a thread chaser on the bung. If you have one for spark plugs, that'll work too.
 
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