Knock sensor and O2 sensor

[jmmax]

I checked my ECU for any error codes and I am getting a Knock Sensor code and a O2 sensor code. I recently read that if you get the KS code with an O2 sensor code that if I replaced the O2 sensor then maybe the KS code will go away (my knock sensor might still work). Is this true? If so where can I get an O2 sensor and is it easy to replace?

[jmmax]

Oh yeah also, the "Check Engine Light" hasn't come on at all. Wouldn't a bad O2 sensor turn it on?

[yelowd]

Wholesale imports on the web has the cheapest price for an 02 sensor ($65 Bosch) that I've found. I couldn't tell you about your codes. Get a haynes or chiltons and then an ohm meter. In the books it will tell you how to check each sensor. 02 sensor should be replaced around 100k or if your header pipe is rotted, so it is somewhat of a maintenance thing. As for the knock sensor, I'd check its resistance and all of that before replacing- they're around a $100 if you shop around.

[jmmax]

Originally Posted by yelowd

Wholesale imports on the web has the cheapest price for an 02 sensor ($65 Bosch) that I've found. I couldn't tell you about your codes. Get a haynes or chiltons and then an ohm meter. In the books it will tell you how to check each sensor. 02 sensor should be replaced around 100k or if your header pipe is rotted, so it is somewhat of a maintenance thing. As for the knock sensor, I'd check its resistance and all of that before replacing- they're around a $100 if you shop around.

Thank you for the info. This was the first time I have ever checked my ECU codes. After I checked the codes I reset my ECU. I drove for 3 days without checking it and finally decided to check it again to see if the codes were still there. I checked it and it said that I had no engine problems at all. No more knock sensor or O2 sensor codes. Does anyone know why this could be?

[mscmor]

the codes may be coming and going, and not setting for a long enough period of time. one sensor or the other may go completely bad in the future. depending on how the software in the ecu is written codes that are set may clear after a number of ignition cycles or instances of no fault detection (what ever that period of time may be)... if the check engine light doesn't com on it's probably nothing to worry about.