Check Engine Light

[neumannu47]

The check engine light is illuminating from time to time on my 2000 RX300. It may stay lit for a day or for a week. According to the diagnostic code, one of the (front?) oxygen sensors is defective. AutoZone can supply the sensor for $130. How difficult is it to change? The last two sensors I had my shop replace were $500 each. The car runs perfectly, and the gas mileage is normal. I'm thinking that this is another case of the sensor failing instead of a functional part of the car failing.

Of course now I need to determine whether this sensor is the same one that was replaced a year ago.

[djspawn00]

The check engine light is illuminating from time to time on my 2000 RX300. It may stay lit for a day or for a week. According to the diagnostic code, one of the (front?) oxygen sensors is defective. AutoZone can supply the sensor for $130. How difficult is it to change? The last two sensors I had my shop replace were $500 each. The car runs perfectly, and the gas mileage is normal. I'm thinking that this is another case of the sensor failing instead of a functional part of the car failing.

Of course now I need to determine whether this sensor is the same one that was replaced a year ago.

What was the exact code you got? Changing the sensor should not be too difficult at all, no more difficult than changing a very expensive lightbulb that requires a bit of penetrating spray before hand.

[tjmc11]

The front o2 sensor is somewhat easy to chagen because you can easily get to it. Use some penetrating oil first to prevent stripping out the threading. Buy the sensor (shop around though...yours seems a bit high....I replaced mine for about 90 dollars I think), and replace it yourself if you feel confident. Email me @ tjmc11@hotmail.com if you have any questions or if you need photos or video of what you need to do.

[Grumpa72]

I have bought Bosch O2 sensors for two of my cars and they weren't $130. They were in the range of $40-50. There is a special O2 sensor socket that is a nice tool to have. It is the correct sized socket with the upper half partially cut away for the sensor pig tail.

CHanging out sensors is easy if you follow the advice given above about penetrating oil. Forget WD40 - use a good penetrant like Kroil or PB Blaster. I use the latter and really like it.

Once you change it out, don't forget to erase the code.

Gary

[neumannu47]

Thanks for the responses. My wife had the code checked, so I don't know the exact code. Not only will I get the exact code, but I will shop for the best pricing before I take a stab at it.

[tjmc11]

Neumann,

You may want to use a "crows foot" type of wrench end, commonly known as a tubing wrench. It looks like a wrench with a small gap cut in it. They are a useful tool to help prevent stripping the nut / bolt. See the link below for what I am referring to. These are great for nuts / bolts that require a grat deal of torque to loosen. I stripped mine out removing mine and had to tap and dye the hole to place the new one in. Be careful and use penetrating oil. Loosen it just a bit and then tighten it back a few times to work the oil into the threads of the hole.

http://www.sears.com/shc/s/p_10153_12605_0...yword=flare+nut

or

http://www.sears.com/shc/s/p_10153_12605_0...yword=flare+nut

[djspawn00]

Neumann,

You may want to use a "crows foot" type of wrench end, commonly known as a tubing wrench. It looks like a wrench with a small gap cut in it. They are a useful tool to help prevent stripping the nut / bolt. See the link below for what I am referring to. These are great for nuts / bolts that require a grat deal of torque to loosen. I stripped mine out removing mine and had to tap and dye the hole to place the new one in. Be careful and use penetrating oil. Loosen it just a bit and then tighten it back a few times to work the oil into the threads of the hole.

http://www.sears.com/shc/s/p_10153_12605_0...yword=flare+nut

or

http://www.sears.com/shc/s/p_10153_12605_0...yword=flare+nut

or you can just borrow the tools from autozone for free (granted you return the tools to get your deposit back). PB blast works well as a penetrating spray, its best to spray some on when the engine is still moderately warm then wait a half an hour or so before removing it.

[neumannu47]

Further to my original post, I'm told that the error code indicates that the Bank 1 Row 2 O2 sensor is bad. Does that make sense, or have I misunderstand something?

[neumannu47]

Regarding the flare nut wrenches, one of the links above is to standard. Isn't a Lexus all metric, making the following wrenches the correct ones?

http://www.sears.com/shc/s/p_10153_12605_0...yword=flare+nut