Denso 234-4205 Oxygen Sensor

I'm so used to getting counterfeit parts from online that I was very happy and a little surprised to see that this was a high quality original equipment part. I examined the Box closely look for misspellings ended the same in examining the part- it was well machined and was clearly made by the well-known manufacturer that makes very good products. Installed with a bit of difficulty due to tight working space but works absolutely perfectly.

Check engine light came on. Plug in the OBD code reader and it said P0171 indicating fuel system running lean or rich and likely problems with O2 or MAF sensors. Took out MAF sensor (near air filter) and clean it with spray cleaner and no change. Called Toyota dealer for O2 sensor prices and learned that the 2000 Corolla has 2 sensor, one at the exhaust manifold and one near the catalytic converter. Also learned that the exhaust manifold one is the one that goes out most often.Searched online for pricing. Found on Amazon.com; which was much cheaper than the dealer and other autoparts websites. This one was the exact OEM for my car so no adapters were required. I just removed the two attachment bolts, took out the old sensor, put this one in, replaced the bolts and reset the check engine light (by removing one of the battery terminals) and problem solved. Don't recommend the slightly cheaper universal units that have adapter plates that may not work.

This fixed my idle issue and fuel economy issue. Should be a maintenance item but I don't think anyone of us replace them on a regular basis like oil.

Got CEL with P0171 and P0125 codes. Replace upstream O2 sensor with this item and the codes have not come back. Watched YT video for replacement instructions.

I had replaced the upstream O2 sensor on my 2001 Chevy Prizm (similar to the Toyota Corolla) with two Bosch sensors. The first one failed within a matter of days. The second one failed within a matter of weeks. I continued to drive the car with the check engine light on for months. That was a mistake, because that likely caused my new catalytic converter to also fail. When I had to have my car inspected, the mechanic replaced the same Bosch sensor, but I don't know what brand he used. Once again, that sensor also failed within a short time. Finally, after all that aggravation and expense, I found the Denso sensor. I looked at the reviews and learned this is the OEM brand O2 sensor for my car. Nine months later, so far so good. The check engine light came on a few times in that time, but it was not related to the upstream O2 sensor, finally! I wish I got the Denso sensor the first time. I would have saved a lot of money in repairs.

Less expensive then buying from the autopart stores, easy to install and fit perfectly in our Toyota Corolla 2001.

I got this for my 2002 toyota corolla S. Fit perfect and half the price of your local auto store. This is sensor # 1 right after the engine. You might have seen some guy in Youtube using a NGK on his 2001 toyota corolla. He has to get an oxygen sensor wrench and screw it in. Forget that, get Denso and you just slip it in thats it. NO 02 wrench require.. Keep in mine that he has 2001 corolla, I have 2002 corolla S.I was scare too when order something like this online. because you don't know what you going to get..

I thought it was a great value and it is. I didn’t realize what universal meant. Splicing and shrink tubing as it turns out is something that I am not good at. I wasted money and effort. I had to order the complete sensor.

Fits well, and works perfectly

This was the exact OEM part for my Corolla, ad even included the fiber gasket for install. Excellent quality, as an OEM product should be. I tried a cheap aftermarket sensor prior to this one, and the brand new aftermarket sensor still threw the P0135 bank 1 O2 Sensor failure code. After replacing with the Denso OEM sensor, the code never came back. Do yourself a favor and use an OEM sensor with your Toyota...they are sensitive to how quickly the sensor gets up to temp, and aftermarket ones won't always work. Great price on these, Amazon!

Perfect fit

Exactly what I wanted bit expensive though

Perfect OEM fit and function at a great price.