Tundra o2 sensor

Getting a P0155 code from bank 2 sensor 1. From reading other forums it seems that Denso is the way to go, but I guess I’m asking if it’s a faulty sensor or something else throwing that code? Should I have a shop diagnose it?

 

V8 right? Is it 2WD or 4WD?

Can you go in here, and update your "Vehicle One-line description" to this?: 2000 RCLB SR5 V8/2WD (or V8/4WD)?

We don't need to know your truck is red, and if it's "single cab" (regular cab/RC), we know it's a long bed already. But we DO need to know if it's a V8 and if 2WD or 4WD because oxygen/af sensors are variable part numbers depending on whether you're V6 or V8 and whether 2WD or 4WD.

Anyway, that code is for the passenger side upstream sensor. It most likely is failing. You should replace the upstream and downstream on that side at the same time, yes it's more expensive, but it's also "good measure", because they work together, and having old and new on the same bank can lend to other codes throwing that are red herrings.

If you really, really want to know if the heater on that sensor is bad, **IF** the upstream sensors are the same part number for your truck when you look up your vehicle at www.densoautoparts.com, you can swap driver and passenger upstream ... if the code jumps to P0135, you know that sensor is definitely bad. If not, you have a wire/circuit issue. But that's a lot of knucklebusting for those upstream sensors just to get a sanity check.

PS - DO NOT buy car parts on scAmazon or fleaBay, you're liable to get counterfeits. Buy on Rock Auto, Summit Racing, or any other site that doesn't allow 3rd party vendors to sell (i.e. don't use anyone who doesn't monitor or control their supply chain!)

 

Just be glad its bank 2. I found bank 1 connector to be a bitch ....at least w no lift. Bank 2 takes 5 minutes. Yes, only get the Denso. These trucks do seem to eat as toyota calls them " air fuel sensors" wonder if leaky log manifold is a cause for their high mortality.

 

Very fortunate to have two friends with lifts. The ones on rock auto seem to be what I want.

 

Check engine from O2 just... went away on its own? It was p0155. Money is a little tight, how quickly should I be replacing the passengers side upstream-downstream with this in mind? Bank 2 Sensor 1 is the location of the code.

 

Cound your blessings. Maybe you just have some corrosion in the connector, or the harness is rubbing away on something.

 

Forgive my ignorance, and yes I have googled this but I'm sure you understand why I trust (you) guys more; not going to damage the truck? Running with a bad O2 sensor or one throwing a code every now and then? And all of this is said with the assumption that I intend to do this repair ASAP regardless.

 

That specific code is basically saying, "Hey, either the built in heat element on this O2 sensor is kicking out some fucky numbers, or there's an issue with the circuit/wire harness/etc."

Yes, upstream O2 sensors (that code is for passenger side upstream/pre-cat) do help the ECU understand, "Hey, am I burning fuel optimally?" and in many EFI engines, it's how the ECU knows to adjust fuel/air mix, and sometimes even spark. That specific fault would cause issues with open loop, and IIRC, that would prevent the ECU from trying to learn/relearn fuel-related functions. But if it's not there...

The fact it went away is strange. I'd be checking the connector for issues, looking to see if a PO spliced/taped the harness somewhere (maybe installed aftermarket/universal O2 sensor), make sure there's no other obvious issues. Just to rule out glaring problems that could trigger the code. But I'd also be working toward (at least) replacing the upstream now, and maybe the downstream later.

 

Seems that the code will come and go fairly frequently. Maybe this points to an electrical problem? I wouldn’t know. I’ve been able to replicate the problem with highway driving; anywhere from 50-70mph. Figured that might interest you.

 

2024 SR5 owner here, crewmax. At 600 miles, just had dealer replace the O2 sensor, not sure which one I think it's the down stream, it's under warranty so i trust them used OEM, but my question is which company manufactures the 3rd gen OEM O2 sensors?

 

No clue. This is the 1st gen subforum, 1st gen is pretty much what we know in this subforum.

If you want to see if Denso makes it, follow the advice in reply #2. Go to that website and plug in your truck. If Denso is the OEM, it'll tell you in the results.

 

Thanks, sorry for not noticing the subthread. Searched on Denso site, entered 2023 and 2024, nothing

 

Yup. Same here. Dunno what to tell you. Not sure who is making the part, but doesn't look like anything showing up under the Denso name. Maybe that's why the 3rd gens are so unreliable.