O2 sensor?????

how do you check the o2 sensor?????????????

Here's what my manual says:

1. Unplug the O2 sensor electrical connector.
2. Start the engine and run for 2 minutes at 3000 rpm.
3. Raise the engine speed to 4000 rpm and allow the throttle to snap shut (at least 5 times).
4. raise the engine speed to 5000 rpm, lower it to 2000 rpm then turn the ignition switch to OFF. Using a digital volt meter, promptly measure the voltage between the O2 sensor side of the electrical connector and ground. It should be below .4 volts.

Then:

5. disconnect the MAP sensor vacuum hose from the throttle body and attach a vacuum pump to the hose. Apply vacuum and check the voltage again. It should be above .6 volts.
6. If the O2 sensor fails either of these tests, replace it.


Some advise:

Unless you already have a volt meter and vacuum pump, just replace the O2 sensor. The cost of the testing equipment is more than the cost of the O2 sensor itself. On the other hand, if you're like me, just buy the tools. I get excited when my car breaks down, that way I can justify buying more tools!

When replacing the O2 sensor, buy the appropriate O2 sensor socket and thoroughly saturate the base of the O2 sensor with liquid wrench (or similar product) for at least a day! Use the longest breaker bar you can find because if your O2 sensor has never been replaced it won't want to come out! Also, don't try to remove the O2 sensor if the engine is hot.

When I replaced mine, I soaked it for a day with liquid wrench and it still didn't want to loosen. I ended up expanding the end of the O2 sensor socket and rounding the edges of the O2 sensor making it extremely difficult to get out. I finally ended up pulling out the exhaust manifold just so I could break off the end of the O2 sensor and get a pneumatic impact wrench on it!

You probably won't have this much trouble. I've replaced several O2 sensors and my CRX was by far the worst experience I've had.

i dont know anything about cars at all
how do you get to the o2 sensor?
where is the dang thing?


Here's what my manual says:

1. Unplug the O2 sensor electrical connector.
2. Start the engine and run for 2 minutes at 3000 rpm.
3. Raise the engine speed to 4000 rpm and allow the throttle to snap shut (at least 5 times).
4. raise the engine speed to 5000 rpm, lower it to 2000 rpm then turn the ignition switch to OFF. Using a digital volt meter, promptly measure the voltage between the O2 sensor side of the electrical connector and ground. It should be below .4 volts.

Then:

5. disconnect the MAP sensor vacuum hose from the throttle body and attach a vacuum pump to the hose. Apply vacuum and check the voltage again. It should be above .6 volts.
6. If the O2 sensor fails either of these tests, replace it.


Some advise:

Unless you already have a volt meter and vacuum pump, just replace the O2 sensor. The cost of the testing equipment is more than the cost of the O2 sensor itself. On the other hand, if you're like me, just buy the tools. I get excited when my car breaks down, that way I can justify buying more tools!

When replacing the O2 sensor, buy the appropriate O2 sensor socket and thoroughly saturate the base of the O2 sensor with liquid wrench (or similar product) for at least a day! Use the longest breaker bar you can find because if your O2 sensor has never been replaced it won't want to come out! Also, don't try to remove the O2 sensor if the engine is hot.

When I replaced mine, I soaked it for a day with liquid wrench and it still didn't want to loosen. I ended up expanding the end of the O2 sensor socket and rounding the edges of the O2 sensor making it extremely difficult to get out. I finally ended up pulling out the exhaust manifold just so I could break off the end of the O2 sensor and get a pneumatic impact wrench on it!

You probably won't have this much trouble. I've replaced several O2 sensors and my CRX was by far the worst experience I've had.

Since I don't know which model you have, the O2 sensor could be located on the right side of the exhaust manifold (if you're standing in front of the car looking under the hood) or directly on top of the exhaust manifold. The exhaust manifold is a Y shaped piece of cast metal covered by sheet metal which is located on the front of the engine, and is the closest part to the radiator. The O2 sensor is the only thing on the exhaust manifold that has a wire connected to it. The O2 sensor is about the same diameter as a sharpie marker (about 1/2") and about 2-1/2" long with a large nut on the end that is against the exhaust manifold. The wire should be a single black wire coming from the end of the O2 sensor. Follow the wire back to the connector in order to test the O2 sensor.

I would strongly recommend that you buy a repair manual for this car. It's the first thing you should buy when you get a new (used) car. It will give you all the information that you need and will also have pictures and locations of the parts so you can recognize them. If you've never worked on a car before, your CRX will make a great learning car! It is simple to work on and parts are cheap (except for the O2 sensor).

hi I'm the one who replied to your PGM-FI question. How do you know it is your O2 sensor? Did you have someone look at the car? Or are you just going thru the whole car to find out what is wrong.

How do you know it is your O2 sensor?

If the PGM-FI light in the gauge cluster comes on and stays on, it means that there is a problem with the motor. To find out what the problem is you need to check the ECU.

Here's a list of ECU codes, symptoms and causes:

http://www.automotiveforums.com/vbulletin/showthread.php?t=236249