Lexus Trouble Code P1130

[CharBaby]

The Check Engine and Vehicle Stability Control lights are lit on my wifes 01 RX-300. They have come on since we have returned from vacation and the car was sitting idle in the drive way while we were gone. I cleared the the lights by pulling the ECM fuse, only to have them return. I have pulled the fuse twice now in the last three days but the lights keep coming back on within a day. This has happened a couple of times over the years and I usually pull the ECM fuse and all is well for a long time,(2 years). This also happened once when I disconnected the battery to do some PM on the car,(tire rotation and brake inspection), then reconnected the battery when the work was completed. The CEL/VSC lights appeared at that time. I disconnected the battery again and the lights dissapeared and I never saw them again til now.

I drove the car over to AutoZone to have them scan the vehicle and code P1130 has showed up. Their print out states...Lack Of HO2S Switch-Adaptive Fuel At Limit. I went on line under Lexus Trouble Codes and found this...Air/Fuel Ratio Sensor Circuit Range/Performance Manfunction(Bank 1 Sensor 1).

Can someone explain this a bit more to me and possibly explain the exact repair procedure. Sounds like an O2 sensor to me? Kind of wondering why the CEL & VSC light come on together each time! .......TIA

CB

 

[Arradiance]

This is the sensor in the exhaust manifold nearest the firewall. (Bank1 Sensor1) The sensor intially looks like an O2 sensor but it is actually and Air Fuel Sensor (A/F). The big difference between is the A/F runs at a much higher heater temp than the O2 sensor. This is one of the tools that Toyota uses to acheive ULEV. I don't kmow how many miles miles you have on your Lexus but generally this rear sensor lasts about 80K miles.

I have a 99 Avalon that did the same thing and friend of mine had an RX300 that the same thing happened too. If my memory serves me correctly he was also getting some other codes at the same time the sensor went out. They went away after the sensor was replaced and the computer was reset.

The two of use went in together and bought the sensors direct from Denso on their web page. We went for the exact fit model that had the wire and connector attached. I think they the sensor cost around $200.00 a year ago.

He had a garage change his sensor I did my own. You will need to get the special O2 sensor socket from a parts store or online. Go ahead and get the full set of wrenches and sockets for about $25.00. I used both a the socket and the crows foot wrench to remove and replace. You will also most likley need about 1 to feet of pipe to put on the wrench to initially crack it loose. The sensor somes with ant-sieze compound be sure to use it. I had to go after my sensor from the top od the engine compartment because the sterring rack was in the way. You may have more room on a RX300 to come up from underneath, but be ready to have to reach over the fender.

I have yet to replace my front sensor. It seems that for some reason the back one is the unit that always fails. My best guess is becuase of the high heat in the this area.

Hope this helps and good luck!

A

 

[brianl703]

Also check for vacuum leaks. This sort of code can be cause either by a bad oxygen sensor or a vacuum leak.

To verify, you could swap the sensors around and see if the trouble code changes to the other bank.

If it does, it's definitely the oxygen sensor. If not, then it may be a vacuum leak.

 

[CharBaby]

Arradiance,
Thanks so much. This is a HUGE HELP! I will be replacing this soon and will probably do the work myself.

CB

 

[CharBaby]

brian,
Will do! A very good idea before I spend 2 bills.

 

[brianl703]

Might want to check http://www.oxygensensors.com for a better price on the sensors, too.

 

[CharBaby]

Is one brand any better than the other?
Maybe it doens't matter since the factory sensor lasted only 40,000 miles.

 

[brianl703]

I don't think there's much difference between the various brands. I used a Walker in a 1997 Honda Del Sol because it was cheap. It's been working fine for over a year now.

 

[Arradiance]

I took a look yesterday at a couple of sites that sold Air Fuel sensors. They are all running in the $165 to $170 range regardless of make. I went with Denso because that was the OEM on my Toyota.

It is not unheard of for these things to go out at faily low milage. The heater element is the item that goes out on the things. They run at a much higher temperature compared to an O2 sensor. The ECM will give a fault if the heater unit does not reach temp within a specified time. You can clear fault after you start the car, but it will come back after the car cools down and is started again.

 

[brianl703]

Usually there is a separate code for a heater problem. The Del Sol needed a new sensor because the heater crapped out.

Incidentally, I have never, ever seen or heard of a heater crapping out except on Denso sensors.

 

[MaximaGuy]

One quick question, this RX300 engine seems to only give 14/15 miles combined highway and city on some of my buddies RX300's (no SES codes).

Does anyone know what is the exact problem on these 3.0L engines from Toyota?

 

[brianl703]

There are many things that could be causing poor fuel economy that have nothing to do with the engine.

 

[CharBaby]

Arradiance, your correct. After clearing the CEL it does return again after the engine cools down and is restarted. Thanks again for your responces.

brian, Thanks for the web site. This might be the way to go.

MaxGuy, Our RX gets between 17-19 mpg city/hghway. We usually get a steady 22 mpg on a long family vacation with all of us and our gear. Our RX is AWD with a final drive of 3.29:1 as compared to the 2WD with a 3.08:1 final drive. Do your buddies have the AWD version? Also the fact that the RX weighs in at nearly 4,000 lbs and has a very small 3.0 lt./183 cid engine pulling that weight may contibute to the poor mpg. The engine certainly doesn't lack for power though considering the weight. One more thing. Our RX does get slightly better mpg with high test 93 oct. than it does with regular 87 oct. This is the only vehicle that I have ever owned that actually get better mpg with high test fuel and I have been checking my mpg for over 25 years on all my cars/trucks.

 

[surfstar]

Char Baby, as posted in your additive thread, I'd check into the emissions warranty on that O2 sensor. 5 yrs and 40k miles should be within the federal warranty limit.

 

[Market525]

Out of curiosity, what octane fuel does the RX call for in the owner's manual?

I have a friend who recently bought a new VW Passat (mistake, IMHO) and one of the issues he was hesitating on was that VW recommends premium fuel in this car. The dealer actually told him not to worry about that, the engine would adjust itself for the lower octane fuel. He bought the car.

What a bunch of ** from the dealer! Of course it adjusts itself -- by sensing the spark knock and retarding the engine timing - thus hurting fuel economy and performance. GRRRRR ... some of these dealers ....

 

[CharBaby]

Surfstar,
My RX is 5 years and 3 months old and has just a tad over 40,000 miles on the clock. I'll call the Lexus dealership and ask if I'am still within the warranty.

Market525,
My '01 calls for 87 octane fuel which is a change from the '99 & '00 RX-300's which called strictly for >91 octane fuel. My owners manual also states that if higher performance desiered, >91 can also be used...'01 was a change for the RX. Lexus changed the grill a little bit, the tail lights, went from a 15.5 gal fuel tank to a 19.8 and also allowed the use of 87 octane fuel, and a bunch of other little things like options and such.

 

[CharBaby]

I checked the Federal Emission Warranty in my Warranty Information Booklet and for an O2 sensor it's only 2 years 24,000 miles. Other parts are covered for 4/50,000 miles or 8/80,000 miles depending on the part.

 

[CharBaby]

5-12-06. A couple of hours after whiting my last post above^, and while driving around town, the CEL and VSC light have dissapeared on their own. Strange to say the least. Haven't returned all day. I'll see what happens over time. Hmmmm!

 

[CharBaby]

5-16-06. Still OK!