P0125

Need some help, I just spent $3k getting new cats and a vent line in my fuel system replaced….~60 miles later i’m getting hit with the P0125 (ECT) error code…. anything I can check/do on my own in my driveway to avoid taking it to the shop? No rough idle, engine temp according to the dashboard gauge is fine, running fine

 

Check this thread for one place to start:

https://www.tundras.com/threads/p0125-code.147373/

That seems to be the best searching thread titles alone, there are probably more/better answers if you spend a bit searching.

 

Why did you replace the cats? I think they rarely fail.

 

Cats definitely not the issue. Expensive lesson.

 

They actually rusted out. I had an evap engine code and was about to take it to the shop and then they rusted out. it sounded like I was driving a stock car

 

Crazy part is, some people pay serious money to make their truck sound like that

These trucks don't handle aftermarket cats too well, but at the price you tossed out, sounds like you went OEM.

So these trucks have two temp sensors '00-'04. The larger green one feeds the ECU. The smaller grey or black one feeds the temp gauge. Both on passenger side of throttle body. Part# and locations as follows, but note the FSM for your truck has a way to test for functionality! (Other helpful info for you HERE)

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@shifty` are those OEM sensors? Where did you acquire them from? Anything I should pay special attention to when replacing both of them. I took the truck to the shop, told them I had done some research and it I thought it was likely an ECT sensor that is bad. They discovered that my thermostat was faulty, installed a new one. I thought ok whatever as long as its fixed. 58 miles later, check engine light comes back on, same P0125 code. Im now determined to do this myself, not because Im angry at the shop, I just dont feel like going back there and having it sit for a few days.

 

Can't trust shops to solve problems, especially a 'general' (non-specialty) shop, or a service chain. But stealerships will bleed you dry. You'll get better info here because "been there, done that" with so many people that have the exact same truck as you, relatively speaking.

For this, you only need the appropriate deep-well socket to change, although it looks like the green one may have a little protruberance on one side that may make using a socket difficult. The work will probably be easier if you disconnect the intake elbow, if coming in from the side/front is needed.

Yes, both sensors there are OEM, part numbers for each are on the bag and correspond to what you see in the pic. It only applies to 2000-2004 years.

DO NOT BUY THOSE SENSORS ON AMAZON OR FLEABAY. 50/50 chance you're going to get a knockoff and you'll be back to square one, albeit with less money.

Do this instead.

Ignore the prices you're about to see for a sec, just trust me on this.

• Click HERE for the green sensor, and look on the right for "SHOP THIS DEALER" links. Any near you? Make a mental note of how many are driving distance away from you.
• If there is at least one, click "SHOP THIS DEALER" button. See what the actual price they're charging is.
• If there was more than one, tap the <BACK button on your browser and click "SHOP THIS DEALER" button next to one of the other ones; see if their price is better.
• Repeat the above until you find the cheapest dealer near you, then add the part to your cart, then if you also want to replace the other sensor for yoru dash gauge, use the search bar to find part number 83420-20040 and add it to your cart too.
• Checkout, noting you really only need to buy the green sensor, in case you're strapped on cash, unless your dash gauge isn't reading temp properly, then you should swap out the black one too.

***IF*** there are no dealers near you, you can use the https://autoparts.serratoyota.com storefront. Unless you're in Alabama, they won't charge you tax, and they'll ship your parts for free IF your total is over $75.

Why am I telling you to do this, when you could go to the local auto parts store and buy some generic, aftermarket piece of shit for 1/4 the price?

1. Because the cooling system of your truck is critical to the life of your truck.
2. The OEM part has lasted, what - 24 years now? - Just fork out the extra bones now, and enjoy 24 more years of worry-free operation.
3. Aftermarket parts are complete shit nowadays, especially since supply chains got all FUBAR'd during the pandemic ... aftermarket part quality is complete ass now, average part life is 2-5 years.
4. The OEM part is built to spec and specifically designed for your engine, and you'll never need to question, "Is it the non-OEM sensor I installed?"
5. We've seen time and time again helping people on here, where these trucks just do not seem to like aftermarket electronics, specifically (sensors, and electronic pumps, mostly)
6. "Buy once, cry once" often applies in this case, as in, aftermarket part average life is 2-5 years, OEM is typically 10-15+, you're paying more for that longevity, and guaranteed quality/fitment/operation.

If you're super-duper strapped for cash and there's absolutely no way you can possibly afford OEM, there are a few brands you may (no guarantee) generally trust, like Standard Motor Products, Dorman, Delco, Delphi, but there aren't any other other names I'm seeing at RockAuto (Beck-Arnley, Walker, etc.) that I'd trust any farther than I could throw 'em, and agan, DO NOT buy auto parts on Amazon or fleaBay, they're rife with knockoffs and grey market parts. Summit Racing and RockAuto are two great parts sources.

 

@shifty` bought the part from Richmond Toyota, $80 for both sensors, no complaints on price. took the larger sensor out and coolant started coming out. freaked out and threaded it back in. I’m probably just gonna take it to the shop and have them do it. I didn’t expect coolant to start coming out

 

Just get the new one right there ready, and cringe and quick dipsy do switcheroo the new one in, you wont lose much coolant. Of course wait till it's cold. You can do it!

 

A little coolant never hurt anything. Don’t be scared, and know the shop will have the exact same thing happen, only they won’t tell you it happened (because it’s normal!!)