O2 sensor question

[Brian's Toy]

Hi all, my Tundra is a 2000 with 76k on it, unfortunately out of the extended warranty for the O2 sensors. I've already replaced one of the rear O2 sensors and that turned out to be a real b*&ch so I can't imagine what it will be like to replace a manifold O2 sensor!!!

I have a code P0155, which should be the front passenger side O2 sensor.

The problem I have right off the bat is; I can't even see the exhaust manifold O2 sensors?

Do you have to remove the exhaust manifold heat shields to replace these O2sensors? I also understand there is a significant risk of these things breaking off inside the manifold.

Please let me know of any helpful tips anyone might have for replacing these things!

Thanks in advance...

[Djackman777]

I think on the 2000 4.7L, the 02 sensors are located on the exhaust manifold right before the flange.
You're in the wrong section BTW, you'll get a lot more response in the 1st Gen Tundra section. Good luck

[Brian's Toy]

Thanks a bunch Djack, I think I'll post in the correct forum for a start....and I'll take another look under the hood / in the wheel wells.


Thanks!

[Acolytes]

If you can afford it I recommend getting headers. (1) chances are the o2 sensor will strip when trying to remove it from the stock head pipe. Everytime we replaced o2 sensors at the dealer, we would order exhaust manifolds too because we knew it will strip. (2)I don't know about other brands but the JBA headers put the o2 sensors in a very accessible and easy to reach spot in case u need to do new o2 sensors in the future. (3) the added performance from headers compared to stock manifolds. ( I have JBA's on my Tundra and the wife's Tundra and couldnt be happier with them). Everytime a friend has O2 sensors go bad I tell them to get headers (if they have stock exhaust manifolds) and I would install the new O2 sensors while I'm doing the headers. I think JBA dropped the prices on the frist gen Tundras also. Good luck.

[Tundradrenalin]

Brian's Toy, can you review the Toyota Specified Major Emission Control Component Warranty? This warranty is in effect for 96 months or 80,000 miles. Maybe it could be attributed to your Tundra O2's? It covers my Rav4's O2 sensors, but they are replaced and ecu reprogrammed due to malfunction.

just a thought.

[Brian's Toy]

Thanks for all the responses, I'll have to review the exact date I purchased the truck, I just assumed I was out of warranty since it is a 2000. I have that SB hidden away somewhere.

On another note...The thought of replacing the manifolds with headers did cross my mind if the O2 sensors broke off. Are the JBL headers an exact fit? I'm always shy of aftermarket parts after some bad experiences many years ago.

I do have the TRD duel cat back exhaust (I do think it kills some low end torque) but looks and sounds great.

Do headers require any other modifications such as fuel system changes or such?

Anyway, first things first, I'll see if there is any chance I'm still covered under warranty.

Thanks again for all your help

[darren_nh]

I thought Toyota was covering O2 sensor on Tundras to 90k regardless of age. Mine went at 96K so I could use the SB. I suggest you call your dealer.

[Ando140]

The extended warranty was 7 years or 90,000 miles, whichever comes first.
I didn't have any problem removing my O2 sensors. Just let the exhaust cool, then spray some pb blaster around the sensor threads and let it sit for an hour. The biggest threat is cracking the manifolds. Mine made a pretty loud sound when it broke loose (which didn't take nearly as much effort as I expected), but nothing cracked and the new one threaded in no problem. The biggest pain on the passenger side one was unplugging it and plugging the new one in (not much room where the plug is, between the floor & the transmission). Also, make sure you use an O2 sensor socket, makes the job a lot easier.
If you buy the sensor online, I'd recommend buying one for the driver's side too, both of mine went out only a few hundred miles apart.

[Brian's Toy]

Ando140, thanks for your response. I just picked up an O2 sensor socket and some PB Blaster on my way home from work today. I figure I'll try and remove the bad O2 sensor first before buying a new one.

I'll be extremely relieved if I can get it out and replaced...

Thanks again for your help!

[Acolytes]

Every set I've done bolts right up. No mod's.

[Ando140]

Originally Posted by Brian's Toy

Ando140, thanks for your response. I just picked up an O2 sensor socket and some PB Blaster on my way home from work today. I figure I'll try and remove the bad O2 sensor first before buying a new one.

I'll be extremely relieved if I can get it out and replaced...

Thanks again for your help!

Did you give it a try yet? Just curious about your results. From what I've seen on here, nobody that has used pb blaster has had the cracking manifold problems. In fact, I think the only reports I've seen of cracked manifolds are the result of a dealer changing the sensors.

[Brian's Toy]

Ando140, thanks again for your help. The O2 sensor came loose!!! What a relief... I soaked it with PB Blaster, let it sit a few minutes and then started the engine and let it warm up. I was hoping the heat would help the PB Blaster soak in, don't know if it helped of not... After it cooled down I soaked it again and let it sit over night.

I used an O2 sensor socket and it came loose with some decent effort on a 1" wrench but no big cracking sound.

I'm going to go ahead and order 2 of these now since the other exhaust manifold O2 sensor is original.

Thanks again for everyone's input!

[tmlong]

Toyota covered my O2 sensors and even replaced the exhaust manifolds past 70k. Push your dealership to check on the extended warranty guys, they might be charging you, then turning around and charging Toyota.

[Ando140]

Originally Posted by tmlong

Toyota covered my O2 sensors and even replaced the exhaust manifolds past 70k. Push your dealership to check on the extended warranty guys, they might be charging you, then turning around and charging Toyota.

was it within 7 years of the original vehicle in service date?

[tmlong]

Originally Posted by Ando140

was it within 7 years of the original vehicle in service date?

Looking back on it, I would say just barely.