Fuel-Air metering Fault Codes

[markstahl]

Hello,

I have a 98 Camry XLE and recently the CEL came on. i borrowed a code reader from a local Autopart shop and got the following codes, P1133, P1135 and P1130. They all have to do the Fuel-Air metering sensor but it doesn't give specifics. Does anyone have an idea where I can find the Toyota Manufacturers specific code definitions? or does anyone know what these codes refer to? Any help would be appreciated. I am assuming it would either be an O2 sensor or the Mass-Air flow sensor since these deal with air to fuel ratios, but who knows which one!

Mark

[Brian R.]

P1130 A/F Sensor Circuit Range/Performance (Bank 1 Sensor 1)

P1133 Heated Oxygen Sensor (HO2S) insufficient switching bank 1 sensor 1 (Rear Bank)

P1135 A/F Sensor Heater Circuit Malfunction (Bank 1 Sensor 1)

[markstahl]

Brian,

Thanks for the reply but is the A/F sensor the O2 sensor and if so which one?

Thanks

[Brian R.]

What engine?

[markstahl]

It's the V6 with CA emissions. If you have any idea, what's the difference between the air/fuel ratio sensor and an O2 sensor (if there is one)?

[Brian R.]

"is the A/F sensor the O2 sensor and if so which one?" No, they are separate sensors with different functions.

The Mass Air Flow sensor is on the air cleaner housing in the intake tube. It measures the air flow into the engine

The HO2S are in the exhaust manifolds. I believe California models have additional HO2S after the catalytic converter. They measure the oxygen content of the exhaust gases and give the ECM feedback on the quality of the fuel/air mixture.

The term "air/fuel ratio sensor" may be slang for the HO2S. Never heard of it.

[markstahl]

Ok, I'm a little confused now. Are you saying that the A/F sensor in the error code is the Mass air Flow sensor? I found those codes as well and they refer to an Air/Fuel Sensor, not an air/flow sensor. I really would just like to know what I need to replace given the P1130, P1133 and P1135 codes that I pulled from the computer. Thanks again for the help!

[csaxon]

All A/F sensors are air to fuel ratio sensors and measure the combustion gases prior to and during combustion. Oxygen or heated oxygen sensors measure the exhaust gases and are usually positioned along the exhust manifold and pipes. Did your car run out of fuel recently prior to these codes popping up?

[Brian R.]

Originally Posted by markstahl

Are you saying that the A/F sensor in the error code is the Mass air Flow sensor? I found those codes as well and they refer to an Air/Fuel Sensor, not an air/flow sensor. I really would just like to know what I need to replace given the P1130, P1133 and P1135 codes that I pulled from the computer. Thanks again for the help!

My mistake, A/F ratio sensor is another name for the oxygen sensor in the exhaust. See discussion of "Closed-Loop Fuel Control" in the following training document from Toyota Motor Sales:

http://www.autoshop101.com/forms/h44.pdf

Try deleting the codes and see if any return. If they do, it appears you have a bad oxygen sensor.

[markstahl]

Brian,

I appreciate all the info you have provided, but do you know which sensor is Bank 1 sensor 1? Is sensor 1 the one in the front of the car that you can acces through the hood, or is it the one you have to access under the car?

[Brian R.]

I did a little research and found that some 1998 Camrys have oxygen sensors and some have Air/Fuel Ratio sensors - so they are not the same thing and are not interchangeable, although the are put in the same place in the exhaust system. A/F ratio sensors are more precise for providing the ECU feedback for mixture control. I should have read the autoshop101 reference I posted above. It describes the difference between the oxygen sensor and the A/F ratio sensor.

I suggest you call your local Toyota dealer parts department and find out what type of sensor you have and find out what sensor position you need. I believe the sensor you need is in front of the catalytic converter, but I deduced that from a drawing I found.

http://alflash.narod.ru/O2/79062351.gif

and an independent description - where sensor 1 was in front of the cat converter and sensor 2 was behind.

Once you have found out the type of sensor you have and its position, you can buy it from anywhere.

[csaxon]

The left side of engine (radiator side for Toyota) is always bank 2. The right side (firewall side) is bank 1. The heated o2 sensor bank 1 sensor 1 is on the right hand exhaust manifold (rear firewall side) for '98 6 cyl calif camry.

[markstahl]

Thanks for the help in determining which sensor is where. I believe having CA emissions is the determining factor in whether or not you have an O2 sensor or an air/fuel sensor. In looking around online, all the O2 sensors (Air/Fuel) for CA emissions are much more expensive than the standard O2 sensor.

[Brian R.]

Yes, I was surprised by the cost of those sensors.