Quattro15

I've got about 160k on my taco so I figured it was time to replace my O2 sensor. I have searched on the forum and found that I only have 1 sensor but when I called up my local dealer I was told that I have 2 sensors. The one that I located was right in front of the Catalytic converter. The parts guy at the dealer said there is another one "upstream" right where the exhaust system begins.

So my question is who is correct?

If I have both do I need to replace both?

Thoughts??

Thanks guys!

Quattro15

Also...is it possible to clean an O2 sensor so I wouldn't have to replace them?

BigBallsMcFalls

one in front of cat, one behind cat. both under vehicle. none up high or close to the engine


yeah you can clean them with a blowtorch but this is dubious at best. what kills them
is not crud, but loss of the metals which are part of the ceramic element. can't clean that
when the problem is not dirt

Quattro15

Yeah...upon further inspection I found both of them.

When I called the dealer one was 130 bucks and the other was 200 bucks??

When I try to buy them online...like from sparkplugs.com they are both the same price and PART NUMBER.

Is there something I'm missing here?

Where should I buy them from?

Any OEM sensors that are just as good as the dealer ones?

Thanks!

cackalak han

http://www.urdusa.com/product_info.p...uku0pulktjt241

Part numbers vary by year and engine.

http://4runners.org/writeups/02sensor/index.html

BigBallsMcFalls

130 bucks are o2 sensors
200 bucks is the front one, air fuel sensor for cali spec vehicles
if not cali spec then the front is same part number as rear

Any OEM sensors that are just as good as the dealer ones?
yes and no. you may not get the correct one from the clown at the
autozone counter but you WILL get the exact correct one from the dealer

in fact the new ones from a dealer are upgraded. pn 30510 old pn 30511 new. [this is air fuel sensor]

so yeah roll the dice. and you might get the right part. or just get the right part from the start and never look back, or guess, if you end up with a code.


a lot of people suggest URD parts or even a bypass o2 sensor but...if you have the loot just get the original dealer stuff. no guesswork and you will never get busted for trying to evade emissions. I know in Mass or California if you try to fudge emissions and get caught, it is a big ass fine


I ain't rich but I ain't poor either so I always get parts from the dealer. they always work. I once tried to get a sensor from a parts store and they looked it up 3 times and swore it was what I needed. well...it wasn't, and being electric parts... no return, so I was screwed out of 100 bux. I learned that day to never try to cheap out. the thing acted like it was working and wow my truck never ran so good, then the ECU had enough of compensating and blew the codes and it ran crappier than ever. lesson learned

Quattro15

Just got off the phone with my dealership and I was asked my VIN number in order to see what sensors I needed. When I told him he found that I have front and rear O2 sensors....he said they were different part numbers but the same price of $127.07.

I'm with you on better safe than sorry so I'm probably going to go with these sensors unless anyone can convince me differently here in the next couple hours.

Thanks!

cackalak han

Well, I have not ordered anything from URD, so I cannot really vouch for them, but plenty of people have posted that they are legit.

But if you want to buy from a dealership, give TRDparts4u.com a call. They are Toyota of Dallas and their pricing is the lowest I've come across.

saulgoode

Just leave the sensors on there till u get the CEL. I've got 206k on my 4runner and its still getting me decent mpg and not screwing anything else up. I'll get around to changing mine sooner or later.

Quattro15

Saul,
I'm thinking of doing this at the moment. I just got off the phone with my mechanic...who is someone I hold in very high regard with my Yota maintenance.

He said to leave them alone also. That if I'm passing my emissions inspection and don't get a CEL that they are fine and to save my cash for the time being.

Quattro15

I also just read on 4x4Wire.com that the O2 sensor BEFORE the catalytic converter is the one that affects gas mileage and the one after the catalytic converter is there only to monitor the converter and should be left alone as replacing it won't improve your fuel efficiency.

Is this correct?

BigBallsMcFalls

yup, 100% correct.

but if the rear sensor works, and blows a code
that the cat is inefficient, the cat really is inefficient and you won't pass inspection

if the rear sensor is half-working, and blows a code the cat is inefficient, it may not be
the cat, just a almost-dying rear o2 sensor



I got a 0420 code (on april 20th, go figure...prob a jokester ecu programmer) and replaced the rear o2 sensor and
gosh dang that was all it was. new o2 sensor, no codes after 1000 miles. the sensor
was about dead but the code was for the cat. and no other codes letting me know
the sensor was bad. in fact the toyota troubleshooting procedure for any -bad cat- is to first
check connections, then the 02 sensor. before replacing the cat

Quattro15

Good to know!!

I'm going to the beach on Monday...I plan on seeing what my mpg number are during the trip as it's 300+ miles on the highway from NC to SC coast (Black Mtn to Pawleys Island)

I'll let you all know when I get back what I find out.

saulgoode

I'm no certified mekanic by any means but I will say toyotas oem parts do last a long time. The last time I flushed my radiator (3yrs) I changed out the original thermostat with an oem one and I could not tell the difference between the old one and the new one. I could have kept the old therm in there. My thinking with the 02 sensors is keep them in there until you Have to change them.

BIC performance

I just installed a Universal NGK/ NTK sensor on my truck a few days ago, other than not being able to remove the stock one as the nuts were completely rusted and half gone. I ended up just welding a screw in style 02 bung beside the stock one. The truck runs great, I just need to fill the tank again and see if I can get better than 300-320 km's per tank !!!

BTW the downpipe cannot be removed from the truck, without removing the transfercase cross member.

toy_tek

Pretty sure the OEM 02 sensor is a Denso. So is the part you get from URD.

cackalak han

You usually can't tell a difference between a bad thermostats and a good one. Only way to tell if it's a bad thermo is to see if it opens up when placed in hot liquid. (or if your car overheats/never heats up).

I think it's a psychological thing for some people. I do agree that getting OEM for some of the stuff is good (timing belt, starter, trim pieces, etc.). But for parts like this, why spend the extra cash? If it's not that much of a cost difference, then by all means get OEM. But if not....

Gadget

I am pretty sure URD is legit.

http://www.fjcruiserforums.com/forum...-tour-urd.html


The O2 sensor that came on your truck is made by Denso.

URD has Denso O2 sensors and they are the same thing that you get from the Toyota dealer. The only difference is that if you get it from URD it comes in a pretty blue and gold box that says Denso on it and comes with a new gasket. The same sensor from the Toyota dealer comes in a plain brown box that says Toyota on it and cost more.





Gadget

Quattro15

Well I'm back from the beach...it was a blast!! My yota performed flawlessly, no hiccups at all, not that I thought there would be any.

Anyhow...I did the numbers and I was getting around 19-20 mpg with my Leer camper shell on. Good enough for me to not touch that sensor!

Thanks everyone.

Maj

The Denso I purchased was slightly different than stock but the Bosch unit was a very different shape. I returned the Bosch.