woods

Greetings,

The check engine light and VCS light have been on and off lately. Advanced Auto checked the codes tonight.

P1130
P1150

Based on recent research the codes indicate Air Fuel Ratio Sensor Circuit Range/Performance malfunctions in Bank 1 Sensor 1 and Bank 2 Sensor 1.

My questions are: What next? Replace Air/Fuel Sensor?

Thanks!

Lexmex

Woods,

Thanks for bringing the codes.

The P1130/P1150 are indeed just what you mentioned.

There are 3 possible trouble areas:

1. An open/short in the A/F sensor
2. The A/F sensor itself
3. The ECM (doubtful)

From it coming on/off there could be something loose on one of the two A/F sensors, there is a bad A/F sensor, or there are anomolies in the climate/air that are causing this.

You need to do a few things.

1. Pull the EFI Fuse AND the negative and positive battery cables as we have mentioned before. You can put the EFI fuse back in. Wait 30 minutes. That should kill any juice in the capacitors.

2. Take it for 1 hour drive, 50/50 mix of highway/city if possible.

3. See if light comes on or not.

4. If the light comes back on again, you will need to verify which of the 2 A/F sensors is the culprit. Now I am not sure what OBDII readers Autozone has been using, but many mechanics (Lexus/Toyota definitely have them but I don't want you to spend extra $$$) have readers that will analyze the 2 oxygen sensors to see what the readings are and can determine which sensor is the culprit. Some higher end OBDII readers can not only tell you what the error code is, but also which sensor is the culprit.

From general experience I have seen on this forum and in what I have read, the usual suspect is the rear sensor behind the engine block, Bank 1, Sensor 1.

woods

Thanks! Light went out today. Climate changed from wet/humid to dry. I will check the A/F sensors for a loose connection and reset the codes. I will get back later. Anything with it being in Bank 1 and Bank2.

Woods

anulex

dude it going to come right bank. be prepared to spend $400 on the replacing the two a/f sensors

woods

thanks! Can anyone tell me what the toyota part number is? I checked at Adavanced Auto yesterday. All they sale is the bosch.

Woods

Lexmex

Woods,

Go to a place like www.oxygensensors.com and plug in the information for your RX300. They list the Denso sensors (these are the ones you want) and you need the ones that "sensor located in the front manifold/exhaust pipe before catalyst - two required). The other sensor listed is for the one after the catalytic converter below the vehicle, which you don't want.