99 liberty knock sensor

[Insomniac]

Hi,

I recently purchased a low km '99 3rd gen liberty. A couple of days after driving it i was on the freeway with cruise control on and i got a check engine light. It was only on for about 2 seconds then it went off and didn't come back on at all in the next couple of hundred kms. I checked the CEL code and it came up as 22 which i believe is a knock sensor code.

I have limited knowledge about engines. Could the fact that the sensor was only on for a couple of seconds mean i just had bad fuel, a faulty reading or could it mean the knock sensor is on the way out? There was no power loss while the light was on and it is driving normally.

Should i replace the sensor and if so is there anything wrong with getting a generic one off of ebay. Also what part should i get, i think i read that subarus use three different types.

Thanks in advance for any help.

[Robbks]

check the sensor and connections, they get old and brittle.
if damaged, personally, i wouldn't trust the ebay jobs, go to bursons or Auto Service solutions (http://www.efi.com.au) and buy a proper branded one to suit
Bosch, denso, etc

[Insomniac]

Wow that was a fast reply. Thanks for the info.
I was thinking i should reset the codes and wait to see if it happens again, or should i definitely change it asap?

Also do you know I can get a copy of a workshop manual?

[Robbks]

always reset the ECU and test again.

but knock sensor is important in keeping the engine internals in one piece, inspect it and see if there's anything going on

[Insomniac]

Reset the ecu or just reset the CEL codes? Sorry don't really know what I'm doing. In fact I'm only about 75% sure what I'm looking at is in fact the knock sensor. (located just below the throttle cables, looks round with a bolt in the middle.) Don't have the tools to pull it off but I'm going to try to get it done tomorrow.

New to working on engines, but i have always wanted to learn so i can save some money and for the enjoyment.