O2 sensor help and cel codes

I know there are many threads on these and I have searched through many of them.

I have a 2003 tacoma with the 2.4l mt

I have had a list of 8 engine codes intermittent which I can post up if anybody cares to chime in.


Looking to replace the 02 sensors however I am trying to be cost effective for the parts.

My toyota dealer says both the upstream and downstream are Denso and the same part# as well as price. P#89465

However every other part place I have spoken with carries NGK sensors and the downstream sensor is much less expensive.

I went to the extent of contacting NGK support directly.
They stated that the upstream front sensor was #24699
downstream after cat was #24559 (half the price)

Should they be different or the same?

Anybody know anything about this at all? Id like to purchase the NGK as they are less expensive but hope to get some feedback from anyone who has used them.

 

which I could help, haven't replaced the o2 sensors on my truck yet, but that is changing soon, would like to see what responses you get

 

I got mine for my 2004 from Rockauto. They are two different numbers and yes the downstream one is a lot cheaper. See what Rockauto lists for your.

 

This is a common question with a lot of people.

The upstream sensor, though still commonly called an "O2" sensor, is in actuality called an "A/F" or Air Flow sensor. Of course this sounds like something that should be in the intake area. The A/F sensor uses a much more finite and refined range to more accurately measure the content of the exhaust. This allows for a much better control of fuel mixture. That is why it is much more expensive than the O2 sensor located after the cat, that does not require as stringent measuring to do it's job. If a dealership told me they were the same, I would avoid that dealership. lol.

 

A/F is not for airflow. It stands for Air/Fuel Ratio.

 

Thank you very much for the feedback. My truck has also been replaced with an aftermarket catalytic converter.

I was thinking that instead of replacing the 02 after the cat I will just purchase the URD 02 simulator.
Pricing seems similar and it will be easier for me to install since I wont have to take off the rusted bolts.

 

Not sure on the Simulator BUT all I did was pre-soak the bolts for a few days and made dam sure to NOT act like a gorilla when taking them off......the front one was a BIT@h but that was due to location; we used a "heat wrench" for that one...Both were purchased on-line through dealership sites ....

 

I got lucky and mine rusted clean off! No hassle!

 

Herp a derp.... I have called it an Air Fuel sensor so many times, I have NO idea where I got the word Air Flow meter from. Thanks for the correction.

 

Just my 2 cents here...

Everything I have read on the forum says you should only replace O2 sensors with the factory equipped Denso's. Best price I ever found was on RockAuto and you can use a coupon code.

I also have aftermarket cats, magnaflows, that have performed flawlessly for a good 80K miles.

I am in Chicago area, oddly enough the front sensor was an easy 20min job. I couldn't tell what was going on with the rear, you really can't see it unless you drop the exhaust, ended up taking the part and the truck to a muffler shop, they charged me $20 to install it.

 

Thank you Racer, every bit of information is good

 

I have soaked my secondary sensor about 5times now with pblaster and liquid wrench. Neither seems to be doing anything.
I think Ill have to get it to a shop, after the effort I have put in I think its worth having them torched.

My main air/fuel one looks like the bolts have clean rusted off though.

I wish I could get these parts in Canada for the pricing in the US. Rock auto seems great but shipping puts it up a bit to me.

Since they both look original am I better off just doing both of them? Or is this just a waste of money.