Replacing Oxygen Sensor

[PlanetLexus]

Hello

Where to buy the Oxygen Sensor for my 99 RX 300 as i started to get check engine light and checked with local mechanic and he said its the Oxygen sensor.

I also need to know if it is DIY job, if so instructions would be greatly appreciated.

Regards

[code58]

Hello

Where to buy the Oxygen Sensor for my 99 RX 300 as i started to get check engine light and checked with local mechanic and he said its the Oxygen sensor.

I also need to know if it is DIY job, if so instructions would be greatly appreciated.

Regards

P-L, You can probably find a bunch of info on this subject because it has been discussed a lot on the Lexus forums. Get the code read at Autozone or 1 of the places that read for free and post here so we can help you further. Make sure if it is code for 1 of the front sensors that you get Air/Fuel Ratio sensors and not oxy. sensors! It's real easy if it's the FRONT 1- not as easy if it's the rear 1. (Harder to get to). Post back and we'll help you out- quite a few guys here that have had experience with it.

[PlanetLexus]

Hello

Where to buy the Oxygen Sensor for my 99 RX 300 as i started to get check engine light and checked with local mechanic and he said its the Oxygen sensor.

I also need to know if it is DIY job, if so instructions would be greatly appreciated.

Regards

P-L, You can probably find a bunch of info on this subject because it has been discussed a lot on the Lexus forums. Get the code read at Autozone or 1 of the places that read for free and post here so we can help you further. Make sure if it is code for 1 of the front sensors that you get Air/Fuel Ratio sensors and not oxy. sensors! It's real easy if it's the FRONT 1- not as easy if it's the rear 1. (Harder to get to). Post back and we'll help you out- quite a few guys here that have had experience with it.

Thanks

I just got it checked and the code is P0171 Bank 1 System Too Lean message.

I really appreciate your feedback on how to replace it and where to get it.

[z4u]

hi people :D ,

new to this forum, very exciting info on this forum,

i too have a problem with my rx 300 (99),

engine light on 3 weeks ago, got it checked ,turned out to be P0171.

mechanic said need O2 sensors for front & back, advised me not to get it from

autozone but from dealer.

the price difference is huge, dealer wants $250 for each,

autozone $169 front , $130 rear. <_< .

need your help with that ,

also had to take an emergency trip to windsor, canada (about 650 miles) roundtrip.

the light went off after 400 miles, but came back after another 50 miles.

the engine is making kinda roar noise,

every time i accelerate the it sounds like a hotrod.

any advise low mpgs too

thanks ;)

[lenore]

By the way it is probably not the O2 sensor, those are the air fuel sensors on bank 1 and 2...

[code58]

hi people :D ,

new to this forum, very exciting info on this forum,

i too have a problem with my rx 300 (99),

engine light on 3 weeks ago, got it checked ,turned out to be P0171.

mechanic said need O2 sensors for front & back, advised me not to get it from

autozone but from dealer.

the price difference is huge, dealer wants $250 for each,

autozone $169 front , $130 rear. <_< .

need your help with that ,

also had to take an emergency trip to windsor, canada (about 650 miles) roundtrip.

the light went off after 400 miles, but came back after another 50 miles.

the engine is making kinda roar noise,

every time i accelerate the it sounds like a hotrod.

any advise low mpgs too

thanks ;)

Your mechanic was right- don't use anything in the way of sensors, spark plugs or the like but orig.eq. Having said that, you don't have to pay that kind of money for orig. eq. You can find orig. eq. from Lexus online for $150. ea. (if you in fact need both of the front sensors, they are the same). Make certain before you spend that kind of money that your mechanic WAS ACTUALLY RIGHT! By the way, the reason I advised you to use only orig. eq. is because the aftermarket people have done a terrible job of getting the sensor thing right on these cars. No such problem with orig. eq., they work where aftermarket may or may not work properly. There is an excellent site for information on sensor trouble codes and what the cure is as well as a million other automotive problems at www.AA1Car.com

[Grumpa72]

I will disagree on the sensor issue. If the sensors that you see at Advance Auto/Autozone or your FLAP are Bosch or other quality name, I would have no issue using them. I have replaced to oxygen sensors, one in my son't Honda and one in my wife's Ford Mustang. Both worked well and continued to work up until I sold them. If they are generic and no-name then I wouldn't use them.

Gary

[z4u]

I will disagree on the sensor issue. If the sensors that you see at Advance Auto/Autozone or your FLAP are Bosch or other quality name, I would have no issue using them. I have replaced to oxygen sensors, one in my son't Honda and one in my wife's Ford Mustang. Both worked well and continued to work up until I sold them. If they are generic and no-name then I wouldn't use them.

Gary

thanks for the info,

by the way what do you guys think about

the roar(for lack of a better word) is???

[Grumpa72]

Since Lexus, and virtually every other manufacturer I would guess, doesn't make their own filters, spark plugs, plug wires (where applicable), sensors, and a host of other parts, I don't see what is wrong with buying name brand parts that meet the OEM specifications. Do we buy Lexus oil? No (well, at least I don't)! We buy a name brand, quality, 5W-30 that meets the requirement. Do we buy a Lexus oil filter when there are probably half a dozen other quality pieces out there? One of the few things that is in short supply in the aftermarket is ATF, although that is even becoming less of any issue as other manufacturers make a Toyota spec'ed ATF.

If the aftermarket industry is willing to make a product that meets Toyota/Lexus requirements, why do we have to buy something with a Lexus name on the container that was spec'ed and outsourced? A good example is timing belts. You can buy a great belt from Gates that is every bit as good as anything that Toyota ever asked for.

Ok, off the soapbox.

Gary

[AHJGTA]

My experience with non-Lexus O2 sensors was not good.

I got Densos from an EBay Supplier from Miami. I was so happy and slapping myself on the back to get 2 for $50 including shipping to Canada.

I spliced and soldered them. They worked for maximum a day before the Check Engine light came back on complaining about the O2 sensor heater.

Spent $160 at Lexus for one O2 sensor and no complaints at all.

The sensors were identical except that the ones from Miami had holes in the heat shield.

Bad experience. I was considering getting the timing belt kit from Ebay but now thinking of staying with the dealer.

Since Lexus, and virtually every other manufacturer I would guess, doesn't make their own filters, spark plugs, plug wires (where applicable), sensors, and a host of other parts, I don't see what is wrong with buying name brand parts that meet the OEM specifications. Do we buy Lexus oil? No (well, at least I don't)! We buy a name brand, quality, 5W-30 that meets the requirement. Do we buy a Lexus oil filter when there are probably half a dozen other quality pieces out there? One of the few things that is in short supply in the aftermarket is ATF, although that is even becoming less of any issue as other manufacturers make a Toyota spec'ed ATF.

If the aftermarket industry is willing to make a product that meets Toyota/Lexus requirements, why do we have to buy something with a Lexus name on the container that was spec'ed and outsourced? A good example is timing belts. You can buy a great belt from Gates that is every bit as good as anything that Toyota ever asked for.

Ok, off the soapbox.

Gary

[smooth1]

Since Lexus, and virtually every other manufacturer I would guess, doesn't make their own filters, spark plugs, plug wires (where applicable), sensors, and a host of other parts, I don't see what is wrong with buying name brand parts that meet the OEM specifications. Do we buy Lexus oil? No (well, at least I don't)! We buy a name brand, quality, 5W-30 that meets the requirement. Do we buy a Lexus oil filter when there are probably half a dozen other quality pieces out there? One of the few things that is in short supply in the aftermarket is ATF, although that is even becoming less of any issue as other manufacturers make a Toyota spec'ed ATF.

If the aftermarket industry is willing to make a product that meets Toyota/Lexus requirements, why do we have to buy something with a Lexus name on the container that was spec'ed and outsourced? A good example is timing belts. You can buy a great belt from Gates that is every bit as good as anything that Toyota ever asked for.

Ok, off the soapbox.

Gary

That's not altogether true. Denso was seperated from Toyota in 1949, but remains the cheif parts supplier and OEM part developer for Toyota, Lexus, Scion and much of it's racaing division. Much the same as AC Delco for GMC/ Chevrolet and Motorcraft for Ford.

[code58]

Since Lexus, and virtually every other manufacturer I would guess, doesn't make their own filters, spark plugs, plug wires (where applicable), sensors, and a host of other parts, I don't see what is wrong with buying name brand parts that meet the OEM specifications. Do we buy Lexus oil? No (well, at least I don't)! We buy a name brand, quality, 5W-30 that meets the requirement. Do we buy a Lexus oil filter when there are probably half a dozen other quality pieces out there? One of the few things that is in short supply in the aftermarket is ATF, although that is even becoming less of any issue as other manufacturers make a Toyota spec'ed ATF.

If the aftermarket industry is willing to make a product that meets Toyota/Lexus requirements, why do we have to buy something with a Lexus name on the container that was spec'ed and outsourced? A good example is timing belts. You can buy a great belt from Gates that is every bit as good as anything that Toyota ever asked for.

Ok, off the soapbox.

Gary

Gary- have you ever priced compared your choice of aftermarket parts with Lexus/Toyota orig. eq.? Believe it or not there are times when the Denso, Aisin, Mitsuboshi, etc. are actually cheaper than the aftermarket. I have found for the most part the orig. eq. L/T parts to be some of the longest lasting, best parts you can buy. I have spent my entire life in automotive work and can only say that anyone that feels that ALL aftermarket parts that meet the manufacturers specs. (they should) are equal to orig.eq. hasn't been paying much attention. That simply isn't true! My experience is that there are good aftermarket parts and there are bum aftermarket parts. I would bet a ten spot that all 3 of the aftrermarket belts that I have had to scrap because of problems met manuf. specs. Two were made by Gates and 1 by Dayco. I buy aftermarket parts but when it comes to Toyota/Lexus, the orig eq. is of such known high quality, I'm going to stick with them.

Just my 2cents worth.

[artbuc]

Since Lexus, and virtually every other manufacturer I would guess, doesn't make their own filters, spark plugs, plug wires (where applicable), sensors, and a host of other parts, I don't see what is wrong with buying name brand parts that meet the OEM specifications. Do we buy Lexus oil? No (well, at least I don't)! We buy a name brand, quality, 5W-30 that meets the requirement. Do we buy a Lexus oil filter when there are probably half a dozen other quality pieces out there? One of the few things that is in short supply in the aftermarket is ATF, although that is even becoming less of any issue as other manufacturers make a Toyota spec'ed ATF.

If the aftermarket industry is willing to make a product that meets Toyota/Lexus requirements, why do we have to buy something with a Lexus name on the container that was spec'ed and outsourced? A good example is timing belts. You can buy a great belt from Gates that is every bit as good as anything that Toyota ever asked for.

Ok, off the soapbox.

Gary

Gary- have you ever priced compared your choice of aftermarket parts with Lexus/Toyota orig. eq.? Believe it or not there are times when the Denso, Aisin, Mitsuboshi, etc. are actually cheaper than the aftermarket. I have found for the most part the orig. eq. L/T parts to be some of the longest lasting, best parts you can buy. I have spent my entire life in automotive work and can only say that anyone that feels that ALL aftermarket parts that meet the manufacturers specs. (they should) are equal to orig.eq. hasn't been paying much attention. That simply isn't true! My experience is that there are good aftermarket parts and there are bum aftermarket parts. I would bet a ten spot that all 3 of the aftrermarket belts that I have had to scrap because of problems met manuf. specs. Two were made by Gates and 1 by Dayco. I buy aftermarket parts but when it comes to Toyota/Lexus, the orig eq. is of such known high quality, I'm going to stick with them.

Just my 2cents worth.

I have read several reports on various automotive forums which say Bosch & other aftermarket A/F and O2 sensors do not work in Toyota vehicles. I sometimes wonder if people install the wrong part, eg using an O2 sensor where they should be using an A/F sensor. In any event, I only use Denso sensors. They are technically aftermarket because I don't buy them from a Toyota dealer. However, after talking with Denso and inspecting the sensor, I believe Denso aftermarket sensors are the same as Denso purchased from Toyota.

I also agree that aftermarket belts can be a problem. I just went through a major fiasco with my Toyota Avalon which has the same engine as my wife's RX300. After replacing belts, water pump and idler & tension pulleys, I had a terrible noise when I put the car in gear, especially when cold. Thought it was the aftermarket water pump so I went in again and installed a Toyota factory water pump instead of the Gates Tru Flo. No improvement. Also replaced Gates TB with Toyota factory belt. No improvement. Thought maybe I had a bad rear motor mount. Installed a new one (big job!). No improvement. Recently adjusted the A/C belt (as I did on my wife's car to improve her A/C performance). Most of the noise went away. So, it looks like the Gates Accessory belt was the culprit all along. Who would have guessed that??? I am going to install a factory belt to see if the noise goes away all together.

I feel the same way about brake pads. Over the years I have experimented with various brands of hi-end pads. I always go back to Toyota factory pads. I know some say Akebono are the same as factory (sort of like my argument that Denso aftermarket are the same as Denso Toyota factory). Maybe some day I'll give them a try but probably not.

In general, factory parts are worth the extra money, IMHO.

[Grumpa72]

i have read several reports on various automotive forums which say Bosch & other aftermarket A/F and O2 sensors do not work in Toyota vehicles. I sometimes wonder if people install the wrong part, eg using an O2 sensor where they should be using an A/F sensor. In any event, I only use Denso sensors. They are technically aftermarket because I don't buy them from a Toyota dealer. However, after talking with Denso and inspecting the sensor, I believe Denso aftermarket sensors are the same as Denso purchased from Toyota.

I also agree that aftermarket belts can be a problem. I just went through a major fiasco with my Toyota Avalon which has the same engine as my wife's RX300. After replacing belts, water pump and idler & tension pulleys, I had a terrible noise when I put the car in gear, especially when cold. Thought it was the aftermarket water pump so I went in again and installed a Toyota factory water pump instead of the Gates Tru Flo. No improvement. Also replaced Gates TB with Toyota factory belt. No improvement. Thought maybe I had a bad rear motor mount. Installed a new one (big job!). No improvement. Recently adjusted the A/C belt (as I did on my wife's car to improve her A/C performance). Most of the noise went away. So, it looks like the Gates Accessory belt was the culprit all along. Who would have guessed that??? I am going to install a factory belt to see if the noise goes away all together.

I feel the same way about brake pads. Over the years I have experimented with various brands of hi-end pads. I always go back to Toyota factory pads. I know some say Akebono are the same as factory (sort of like my argument that Denso aftermarket are the same as Denso Toyota factory). Maybe some day I'll give them a try but probably not.

In general, factory parts are worth the extra money, IMHO.

Don't misunderstand what I am saying. I was not saying buy Bosch. I was saying buy a name brand part and when I needed them the Bosch worked in my Honda and Ford. I categorize Denso the same way as a principal subcontractor and I will use their parts whenever possible. I had not heard the Bosch problem with Toyota products though. Yours was the first instance I have heard where a Gates timing belt was the culprit. Fwiw, I put one in my Acura Legend 30000 miles ago. Of course, we are talking about a test group of one now.

I will suggest that using quality parts is the way to go but this group and other boards will sometimes give reports that one brand or another doesn't work well in a specific fleet. If that is the case with Bosch then I will cross them off of my short list of potential candidates for the RX.

As a final note, I will say that I have never and will never buy a replacement part off of eBay. The quality, source, and applicability are in question. If I get a part that is wrong, doesn't work properly, or is manufactured wrong, it is easy to take it back to my FLAP and get it exchanged. Can't do that easily with eBay.

Are there other brands of parts that don't work well in our cars? The RX is now over 40000 so I need to keep a list of which one work and don't work.

Gary

[code58]

i have read several reports on various automotive forums which say Bosch & other aftermarket A/F and O2 sensors do not work in Toyota vehicles. I sometimes wonder if people install the wrong part, eg using an O2 sensor where they should be using an A/F sensor. In any event, I only use Denso sensors. They are technically aftermarket because I don't buy them from a Toyota dealer. However, after talking with Denso and inspecting the sensor, I believe Denso aftermarket sensors are the same as Denso purchased from Toyota.

I also agree that aftermarket belts can be a problem. I just went through a major fiasco with my Toyota Avalon which has the same engine as my wife's RX300. After replacing belts, water pump and idler & tension pulleys, I had a terrible noise when I put the car in gear, especially when cold. Thought it was the aftermarket water pump so I went in again and installed a Toyota factory water pump instead of the Gates Tru Flo. No improvement. Also replaced Gates TB with Toyota factory belt. No improvement. Thought maybe I had a bad rear motor mount. Installed a new one (big job!). No improvement. Recently adjusted the A/C belt (as I did on my wife's car to improve her A/C performance). Most of the noise went away. So, it looks like the Gates Accessory belt was the culprit all along. Who would have guessed that??? I am going to install a factory belt to see if the noise goes away all together.

I feel the same way about brake pads. Over the years I have experimented with various brands of hi-end pads. I always go back to Toyota factory pads. I know some say Akebono are the same as factory (sort of like my argument that Denso aftermarket are the same as Denso Toyota factory). Maybe some day I'll give them a try but probably not.

In general, factory parts are worth the extra money, IMHO.

Don't misunderstand what I am saying. I was not saying buy Bosch. I was saying buy a name brand part and when I needed them the Bosch worked in my Honda and Ford. I categorize Denso the same way as a principal subcontractor and I will use their parts whenever possible. I had not hear the Bosch problem with Toyota products though. Yours was the first instance I have heard where a Gates timing belt was the culprit. Fwiw, I put one in my Acura Legene 30000 miles ago. Of course, we are talking about a test group of one now.

I will suggest that using quality parts is the way to go but this group and other boards will sometimes give reports that one brand or another doesn't work well in a specific fleet. If that is the case with Bosch then I will cross them off of my short list of potential candidates for the RX.

As a final note, I will say that I have never and will never buy a replacement part off of eBay. The quality, source, and applicability are in question. If I get a part that is wrong, doesn't work properly, or is manufactured wrong, it is easy to take it back to my FLAP and get it exchanged. Can't do that easily with eBay.

Are there other brands of parts that don't work well in our cars? The RX is now over 40000 so I need to keep a list of which one work and don't work.

Gary

Hi Gary- I buy a lot of stuff online- some of it from e-bay, but a lot of it from other sources that sell orig.eq. parts at discount. I'm a stickler for detail, so I do a lot of research. I used a Dayco a/c,alt. belt on my last belt fiasco because the orig.eq. belt is a Toyota- made by Dayco. After a few days my DIL informed me that it had developed a bad screetch for 1/2 to 1 sec. at startup. I thought it was the a/c comp. going bad (120k), but when she said it did it even with the a/c shut off I started looking elsewhere. 1st. thing checked was the new belt tension- less than 1/2 in.deflection with pressure. No problem there. I spent the next 1&1/2 days pulling the front of the engine off to check water pump, idler pullys, alt, comp., every thing I could possibly think of with a stethescope, and visually. Tearing my hair out, I could find nothing wrong. The thought came to me to put the old belt back on (was in good shape). Installed it with the same tension I had used on the new belt- problem gone! I was not a particularly happy camper. In examining the new belt (even micing all dimensions) it appears the angle of the cut on the grooves is slightly different than the old belt or the grooves in the pully. To top it off, I paid $22.+ at Pep Boys and Lenore said he bought the same belt from Tex. Lexus dealer (orig. eq.) for something like $12.+, retails for $15.+. There are a lot more reasons why I

try to stick with orig. eq. :( Roger

[z4u]

i cleaned my MAF with CRC MAF CLEANER from autozone,

seems thatthe acceleration has picked up , but the sound("roar") is still present,

anybody with any opinion????

thanks

[vicmar]

I also have been told I have the same PO171 sensor issue on my 2000 Lexus RX300...where is the upstream sensor located?  The downstream is easy to find.