Oxygen Sensors

There are 4 O2 sensors or the 4.2L V6 F150: 1 on each exhaust pipe just after the manifold junction & 1 on each exhaust pipe just after the catalytic converter.

The oxygen sensors located before ( upstream ) of the catalytic converters are used to " sense " the amount of oxygen in the exhaust to adjust the air / fuel ratio for the engine

You will have to have access to a scan tool. Autozone does this for free. Bank1=drivers side bank2=passenger side sensor1=before Cat convertor sensor2=after Cat. convertor also referred to "up stream" and "down stream" This just means before(upstream) or after(downstream) of the Catalytic convertor Piece of cake

They are located on the exhaust right before the cats.

Honda oxygen sensor is usually positioned in the exhaust manifold downpipe before the catalytic converter of your Honda vehicle or in the middle of the two mentioned components.

For more details:

http://sites.google.com/site/hondarepairsite/home/2004-honda-oxygen-sensor

This answer will first describe the exhaust system of the 2000 Toyota Echo and then attempt to describe where the oxygen sensors are located.

The exhaust system of the 2000 Toyota Echo is a two piece unit. One piece is the muffler with a little piping at either end (located at the rear of the vehicle - the rearmost bit is open pipe from which exhaust exits the vehicle). The other part extends from the muffler all the way to the engine area of the vehicle.

Starting from the muffler and working forward with the exhaust system one sees two bits of the front pipe that are larger in size than the pipe itself. These bits are the resonator (located near the middle of the vehicle) and the catalytic converter, located toward the front of the vehicle (but still well behind the engine area.

The oxygen sensors are located in front of and behind the catalytic converter mounted into the exhaust pipe itself. The sensors have wires coming out of them - when looking at them for the first time, looking for something with wires attached sticking out of the exhaust pipe is a good way to find them.

If the author remembers correctly, the frontmost sensor (closest to the engine) comes out of the exhaust pipe toward the driver side while the rearmost sensor comes out toward the passenger side.

Sensor 1 is the sensor closest to the front of the car and the other sensor is sensor 2.

Bank 1 is the passenger side of your engine on your Mountaineer

Sensor 2 would be after the catalytic converter ( downstream )

Bank 1 for 2005 maxima is rear part of the engine.

buy one and put it in

One... It's screwed right into the exhaust manifold. It's very easy to get to but can be hard to get the old one out... They make special sockets for O2 sensors.

I own a 97' geo but have two sensors...

From 1996 on, the system is OBD-II, which has two oxygen sensors, one on the exhaust manifold and a second one on the catalytic converter. Pre-96 only have one on the exhaust manifold. The sensor wiring varies with 3-pin and 4-pin variations.

these are sensors on the outside case of the transmission - on the left side/ drivers side 1 is above the CV halfshaft (axle ) the other is about 5" behind it -- each sensor has 2 wires going into it -- the negative and positive. these things are made of plastic and are easily removed with a socket. They also control the shift points -- they make the transmission shift.

There are 2, one before and one after the catalytic converter.

There are 2. Both are on the exaust pipe before and after the catalytic converter.

Do you mean fuel sender? If you do it's located in the fuel tank and is a complete unit (pump & sending unit).

It is on top drivers side just right of the exhaust manifold. It has one bolt and a cannon plug that has a clip that has to be removed before you can take it off

Either your muffler or resonator has corroded and the the fiber is no longer held securely by mesh. The fiber has blocked your muffler and in addition to considerable power loss, you will experience high fuel consumption. If you attempt to drive fast by using a fair bit of throttle your engine will run hot.

Locate the sensor on the exhaust system unplug it ,unscrew it and replace it in reverse. Pretty simple. Autozone will lend you a special socket needed to go around the wires if needed

you have three oxygen sensors, 2 on the front and rear exhaust manifolds, right past where the pipes are connected together. and one by the catlyc converter good luck paul g

I'm not understanding the code of 20, your 1997 Saturn has an OBDII computer. you need a code reader to get engine codes. you cannot pull codes manually by shorting terminals A-B anymore. every one of your engine codes is atleast 3 digits, and should start with P. for example: a faulty oxygen sensor with no responce will show a code of P0134, or a EGR with insufficient flow will show a code of P0401.

Answer

My code book shows that an OBDII code of P0020 is a camsharft position actuator circuit bank 2. you have a sensor problem or your cam chain has stretched beyond the tensioner's ability to remove slack. I was getting camshaft position errors and had to replace the cam chain and tensioner.

this answer is out of the haynes code book. code 35 idle air control valve or cicuit. Or idle speed control switch or circuit(shorted). good luck

One tip on the Idle Air system on GM's - some need to have a special reset on that part to clear the code. On the 1980-1990's GM's the procedure was to drive the car at a speed exceeding 50 mph for a minimum of five minutes, continuous. You will need to make sure the car stays above 50 for the full five minutes. Make sure to find a nice stretch of open highway where the legal speed will let you do this. This will cause the computer to push the idle air system wide open, then fully closed, to check it over the whole range. After this you can clear the codes and the code should not come back.

If it does, cleaning of the intake may help, since dirt in the passages can affect this system also.

If its a 4x4 and 3.7 there are 4 snesors. 2 on each side of the motor. That is what I have. I am changing the ones before the converter today.

Sensor 1 would be before the catalytic converter ( upstream )

Sensor 2 is after the catalytic converter ( downstream )

You are running too rich. the mixture of fuel and air has too much fuel in it,

lead