**********Air Fuel Sensor Bank 1 Sensor 1**********

so letme get this straight.. is this a costly sensor? and is it difficult to get at to replace? I know to buy the OEM part.
I was hoping it was just a dirty Mass air flow sensor or O2 sensor but from what I've described u think its an air fuel sensor?

 

That would be my best guess.

Everything you need to know is here: https://www.clublexus.com/forums/rx-...el-sensor.html

About $100 from Amazon.

 

Brabbit, if I'm not mistaken Air Fuel Sensor Bank 1 Sensor 1 is just a fancier name for the 02 sensor.

 

It`s an air/fuel ratio sensor. Only o2 sensor is after the main cat.

 

great thanks for your help guys... I'm going to look for this on ebay ... my repair guy said hed put it in for me and doesn't have a problem with me bringing in the part. Do I look it up by part number or just search for rx300 air/fuel ratio sensor?

 

I also wanted to give that pennzoil a try.. do u reccommend this for my 99 rx300. 93000 miles

 

brabbit -
i got my sensors from here
http://www.densoproducts.com/results...ctCategoryID=2

 

Pennzoil Platinum 5W30 would be a good oil to try. I am testing out the Pennzoil Ultra 5W30, but still haven't made a decision whether to recommend this oil or not...need several thousand more miles.

 

should i get the rear super class?

 

http://www.amazon.com/gp/product/B000C5YCZ2

 

thanks... it's been great having u guys all help me out. I appreciate all of the info you guys have given me. ( carguy, carver, lexmex). I'll keep you all posted

 

Brabbit. I'm late coming in on this thread but I found it interesting to read through. Your experience has been much like mine.

Part One: My check engine light came on shortly after I bought the vehicle. (120,000 km) A short time later I began experiencing increased fuel consumption and surging when i was traveling with little load on the engine. I replaced one air/fuel ratio sensor after the other and only stopped when the cycle started over again. (I still have the original sensors (there's probably nothing wrong with them) on my shelf.) It was after replacing the final sensor only to have the check engine light come on again, that I decided to take the car to the dealer and pay the $65. to have them check it out. I got the same response as you. "You have a leak in the muffler system and it has to be fixed before we can address the 'check engine' light. The quote to repair the muffler was.........expensive!!!

Part Two: I searched the internet for an after market replacement muffler. Found one and went to the muffler shop to discuss the issue. The mechanic there started the car, put it on the hoist, covered my exhaust pipe with his hand and the leak was immediately discovered by the noticeable 'hissing' sound coming from the hanging hooks welded to the muffler pipe. (Interesting that you would have a break at the same location as I did.) $20. later, the hole was welded shut and after clearing the codes, the light went out and did not return. (Now have 210,000 km)

Conclusions:

Don't assume you have malfunctioning sensors. Unless you have damaged them in some way, they are probably working OK. Having said that, I do know that they must be removed before doing any welding in the area as the gases produced by the welding process can damage them.
The sensors are very sensitive. The leak in my system was unnoticeable until back pressure was created by covering the exhaust pipe.
They also really work. The surging experienced is the result of the CPU taking the reading from the sensors and attempting to compensate.
Be careful to whom you take your car for repairs. I spent over $800. at a well recommended performance garage where they replaced the WAF sensor and (supposedly) the titanium plugs, only to have the 'check engine' light come on as I left their parking lot. After further discussion, it was apparent they had no idea how to correct the problem. (That's when I started replacing the sensors myself, one after the other.)

If you haven't yet resolved your problem, check the muffler system again to be certain there are no leaks. Then go back to the dealer for an assessment. Don't approve any work unless you know it can't be done by a private garage.

I am interested in hearing how things turned out for you.
Good luck. Lockie

 

I had check-engine light in Feb. and took the vehicle to AutoZone shop and had the P1130 reading. In the computer printout and the "probable cause" section, vacuum leak is the second in the list before "faulty AF sensor heater circuit" and "failed AF sensor". I bought the gasket/seal ring from rockauto.com and fixed the joint leak between the y-pipe and the main cat. converter, where the spring-bolt combination is used to connect the two separate parts. After the leak was fixed, the check-engine light went off immediately and it has not returned so far. I still have the new denso AF sensor (purchased on amarzon.com) in the garage.