Temp Sensor

2002 Tundra started misfiring and threw a p0125 code. The temp sensor I removed was broken and bought a new one. I was surprised to see the OEM sensor I bought was different than the one I removed. The one I removed was plastic while the OEM was metal. Furthermore, the OEM sensor does not fit in the wiring harness and I am having trouble tracking down the sensor that I pulled. Anyone seen a plastic temp sensor like this before?

 

Comparing the two

 

I haven't seen anything like that before. Where'd you pull it from? Your truck description you include in your profile gives us almost no critical info on the truck, like whether it's a V6, V8, 2WD, 4WD, regular cab, access cab, etc. So which is it, that way we know what engine you're dealing with?

If V8, your truck should have two temp sensors, one with a black plastic top, one with a green plastic top, I think both have brass bottoms. Both are sitting on the passenger side of the throttle body. One is for the ECU, which is the one you need to replace, the other is for your dash gauge. I can get a pic, gimme a sec.

 

I believe this should be accurate for your truck if V8. Black one on the left (7 o'clock in the circle) is for your dash gauge. Green one on the right (1 o'clock) is for your ECU, which is the one that's throwing the error.

You DO NOT want to use non-OEM parts here. And you DO NOT want to order these parts on scAmazon or fleaBay, you're liable to get knockoffs/counterfeits, any electrical sensor you buy on those sites is questionable. OEM part numbers follow this photo, courtesy of @Tundra2.

You should be able to order the parts online direct from Toyota and pickup at a substantial discount via https://autoparts.toyota.com

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My apologies for the lack of information. It is a v8 and the plug was pulled from.where you stated: passenger side throttle bottle and it is the front ofnthe two sensors. When I pulled it, it was obvious to see it failed as the plastic is completely cracked.

 

In that case, it looks almost like you pulled the temp sender out of its brass housing?! Do you see the brass housing is still intact on the block?

If it's the black one, that should be for your gauge, not your ECU.

 

I ordered OEM and received this from Toyota. Neither what I pulled or received is green.

 

I will go take a pic of where I pulled it. Not sure I saw the brass come off woth it.

 

Yeah, I think you got the wrong part number on this one? See part numbers I posted. I think the one you pictured is maybe for the V6? I'm not 100% certain on that.

If you can PM me your VIN I can confirm part numbers for you. Or you can just look it up on your own using the parts lookup thread, the bulleted points at the top here: https://www.tundras.com/threads/howto-use-the-toyota-parts-system-to-find-order-parts.113808/

Even TPD is showing different part picture.

 

Oh, and just because it's something that should be asked ... are you certain your t-stat isn't stuck open? I'm still also stumbling on the misfire thing, I don't think this should cause a misfire, but that's another story.

According to the FSM, which is readily available for download, p0125 is one of those cases where:

• If the ECU temp sensor (green one, not the dash gauge sender) is bad, it will often throw additional codes (P0116, P0117, P0115)
• If you're not getting additional codes, it's probable your thermostat is stuck open and not letting the engine warm up sufficiently

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I looked up the number you gave me and it said it will not fit my truck and directed me to the sensor I bought. Weird part is I just found the brass top you mentioned (thank you) and it has a part number on it that does compute with toyota: 39422-30030. So tracking that down now.

 

I am planning on doing plugs, coils, and thermostat as well but this is where I am stuck.

 

Gotcha. I think several of us here are eager to follow along on your journey. If you buy your coils under the Denso brand name from RockAuto or Summit Racing or similar, they're the exact same as you'll get at the stealership, but for far less money, and usually better pricing than other online stores.

I personally prefer NGK over Denso on plugs, if you're replacing, I can't recommend NGK Iridium plugs enough.

Coils rarely fail more than one at a time. I'd do the plugs first, and if you're still throwing a misfire code, try swapping the coil for that cylinder with the one next to it, and see if the misfire code changes. If not, coils are not your problem.

I think you mean 89422-30030. Coolant temp sensors are under part category that starts with "89422" nearly always.

 

My apologies, it is 89422. Working in the 30 degree winter has me typing fast. I'll keep everyone up to date on what happens and I appreciate all the help and insight.