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Hey guys, couple of things i've learned, my current challenge, and a question.

I've gone through 3 new sets of front o2 sensors from Atlantic British (who were kind enough to send me a replacement set).

Here's what i've learned: my codes were for "no activity" at both of the front o2 sensors. I replaced them, no codes the next day and truck ran fine, then couple of days later notice the rich smell of gas and what do you know, "no activity" again. Did this one more time after cleaning up the connectors a little and same results, no codes and ran great for a day (max) and then running really rich and no activity once again.

Since then, i've put a little more effort into this and checked the connectors for power - good, then did the pinouts for each of the other 3 wires from the connectors to the ECM - all good, all had continuity and little resistance.
So after doing my homework I now know that my connectors have power and clear signal to the ECM.

So why are my O2's going dead shortly after installing? After talking to several LR mech's and a couple of current LR master techs, the only suggestion was oil/coolant dripping into the connector and killing the oh-so-sensitive heating element of our o2 sensors. Well, that was a very likely cause since I've had a small/slow leak coming from the back (seemingly rear crank seal). So, I take out those new/dead o2's, clean out the connector with brake cleaner, then CRC electric cleaner, then dry air compressor, install more NEW o2's, wrap them completely with electric tape and zip-tie up and out of harms way....

DEAD AGAIN! Hah, at this point it's almost funny...ALMOST. Anyways, talked to a master tech again and now i'm going to more thoroughly clean out the connectors (take out the plastic housing) and really get it spotless, as he said even the smallest drip or oil residue can/will kill these and he still see's it quite often.

I will see if the 2 set's of seemingly dead o2's come back to life, otherwise I'll be ordering new one's from BP of Utah shortly. Which leads me to my question:
has anyone tried/used/heard about BP of Utah's $55/ea aftermarket front O2 sensors?
I know they aren't THAT much cheaper, but at this point, every dollar towards o2's counts, and i've used their orange connector rears and they've worked just fine. I'm staying away from just grabbing universal sensors off ebay or anywhere, but I'm interested in trying these out to save $30.

I've attached BP of Utah's picture of their "aftermarket" O2 sensor...can't see a brand or any info, going to call them soon.

 

Considering the crank is at or above the level of the O2 sensors, and there's a bell housing in the way, this is quite unlikely. I'd check valve cover gaskets and if you're weeping oil out of the head gaskets.

 

I'm really only looking for info, suggestions, and experience with the o2 sensors, and if anyone knows anything about BP of Utah's aftermarkets...and I meant front crank seal, as it appears to get blown back onto lots of stuff over time. But even that has stopped leaking since the switch to 15w40. The point of my long shpeel was that the last set of sensors were definitely NOT dripped on...they only could have been killed by some excess oil that I didn't clean out.
But the headgaskets were recently done along with every gasket and seal except for the cranks.

 

Just a comment, when I bought my truck the O2 sensors and their plugs (and everything else in the engine bay and backwards) was caked and soaked in oil. The inside of the O2 plugs were absolutely coated in oil. The point is they are still working after I cleaned everything up. I can't see how a drop of oil (or a barrel of oil) can kill them after seeing what mine looked like. See if you can seal your O2 connectors with heat shrink, but IMO it's not oil that is killing it.

 

I have a hard time believing a little oil will do this as well.

Let's consider the fact that most of them are soaked in oil not just in DIIs, but in everything because motors leak. That's what they do. Also, how many times have those on here had their O2's completely submerged while driving? More times than I can count for me.

Also, long before an O2 heater shorts, it should be blowing the fuse. If its not, you have another issue.

 

Exactly my thoughts. I thought for sure the cleaning job I did would cancel that problem out, yet the master tech's and current LR tech's said to clean it again.

My question is, if I don't have any blown fuses (which I haven't any of the 3 times so far), what else could be causing these o2's to go from properly functioning to dead or "no activity"? I've watched the live data once I hooked up the new ones and let it run, heat up, revved up, etc and they appeared to be working properly within spec and the truck wasn't over-fueling. Then, a day or two later (possibly hours later as my CEL bulb is still pulled) its not working...

Frustrating. Anyone have any other ideas or things to check?

 

I agree, i've hardly heard of these sensors being "sensitive", they can handle up to 1600 degrees.
the question is, WHAT all can that "other" issue be? What else to check?

 

Check your mass air censors, and your map censors, if either one of these are bad it can cause the cats to run really hot wich can cause your O2's to go bad.I would take it to auto zone or some other parts store to run the O.B II computer to see what codes show up, as I had a code on mine , not enough fuel, bank one,= the O2 censor on the drivers side closest to the engine.I cant see how oil, or for that matter any fluid can ruin the censor, as the heat from the exsust would burn any oil off unless the oil was really bad, and all four would end up going bad.

 

The ECU leaving the heater on constantly until it burns out, unfortunately.

Other than mechanical damage to the wiring, that's pretty much all you're left with for the heater itself.

Damaging the sensor can be a whole host of engine/fuel issues. I'm actually not clear on what the problem is here....heater or sensor.

 

That's an interesting thought. Wouldn't the O2 sensor eventually get up to temp and start working? Or does the ECU just give it the "no activity" code if it senses the heating element portion of circuit is toast?

If the ECU is leaving the heater on, then what? Can it fixed? Reprogrammed? Or replaced?

Brandon - have you tried Ohming out the heating circuit on the old "bad" sensors? If it's open? You know its toast.....Ohm out a new one for a reference.

I am having a similar problem. I am going through a O2 sensor about every three months on upstream, bank 2. I too thought that oil was "wicking" down the wire (inside) and screwing up the sensor. I installed a Bosch Universal O2 sensor. Used the leads from the old sensor and the 2 foot leads and connector that came with the universal. This allowed me to loop the wire and tie it away from the engine and should eliminate this possibility.

I have my "bad" sensor in the garage. I will Ohm mine out.........