anamono

Hi all,

I'm new member of the forum as I recently acquired an MY03 AP1 S2K in Silverstone Metallic with around 100,000 Kms (60,000 miles). The car has been great for the past week other than for the CEL that came on today. Before the light came on I noticed the the car running a bit rough at idle (RPMs dropping). Once the light came on I started noticing that it's definitely idling poorly. Mostly when engaging first from a standstill sometimes leading to a stall. When I turned the AC on it seemed to run better. Also, at high RPMs and full throttle it's business as usual. I checked the oil and it was a bit low right around the low mark on the dipstick. I'm doing an oil change/diff and tranny flush this week. I'm just waiting for the diff fluid and oil to arrive from AMSOIL. So until then I added about half a quart of a generic brand synthetic 10W30.

I will have an auto centre pull the code tomorrow hopefully. But I just thought I'd start this thread and update it once I get the code. Until then please feel free to share ideas and knowledge on what this might be.

Edit: code is P0325 Knock Sensor (KS) Circuit malfunction.

s2k-tilldeath

Could be a misfire. That was the symptom I had when I had a misfire. I did a valve adjustment and it fixed mine. First off before you ask questions at least check the CEL with an obd2 reader to give us a heads up on the code.

anamono

Ok, so I checked the code using a paperclip. I got 2 long blinks and 3 short ones. So using this, it's code P0325 (Knock Sensor (KS) Circuit malfunction). So, my knock sensor went bad all of a sudden? Or is there a chance that this problem is related to something else?

anamono

So, after reading up a bit, it seems like I should check my knock sensor to see if it's broken in an obvious way. But I don't have access to a lift. Is it too hard to find it with the car on jack stands? And I've noticed that a lot of people seem to have their knock sensors break after a clutch change. Now, as far I'm aware the car hasn't had any clutch or tranny work recently. So, I'm kinda puzzled why the sensor would break all of a sudden.

anamono

I checked the code with a scanning tool, and it's the same. Code P0325. So now I'm just on the search of an OEM knock sensor. New or used. Also, I reseted the ECU after I pulled the code, and the light came back on again after a driving for a couple of minutes. Has anyone had this issue not being fixed by just replacing the knock sensor?

Utah S2K

Did you add gas prior to the problem appearing? Knocking may be associated with low grade (i.e. less than 91 octane) or blended fuels. Blended fuels in Canada may contain MMT an octane booster which can throw this code. Oxygenated fuels can also be problematic. Ethanol max10%. MTBE max 15%. Methanol max 0%. Check the owners manual and make sure what you are running is correct.

Utah

anamono

Actually, when the light came on I was on empty heading to a gas station. I filled up a week ago same gas station (premium gas) not sure about their octane rating but I really don't think you could get any higher octane than that within the city.

Anyway, I jacked up the car today and managed to locate the knock sensor. Once I put my hand on it the thing was really loose and came off right away. So it's obviously broken. I managed to disconnect the green part from the connector but the other part is still intact to the engine as I don't have a socket extension of the right length. The one I have is too long. So I'm gonna get the proper extension tomorrow and try and locate an OEM knock sensor to buy. Replace it and hopefully that'll solve the CEL and no more idling/stalling issues.

Picture of the green part:

anamono

I received a used OEM knock sensor that was posted for sale in the classifieds. Replaced it today. Reseted the ecu following this. Turned on the car and it seemed to idle the same way as before kinda rough and almost stalling when engaging first. Went for a 30 minute drive and within 5 minutes the idling and stalling issues disappeared. I don't really understand why they didn't disappear right away but I'm glad that they eventually did. And the CEL never came on. One thing to note is that when I first start the car and release the clutch pedal the RPMs still drop quite a bit. So, is this normal? I don't remember if it used to do this before knock sensor CEL came on.

Threads that helped me along the way:

Knock sensor location from with the engine out
Short guide

Hopefully I won't see this issue again.

MR.T

Did you happen to do the idle relearn procedure after resetting the ecu? If not, you can expect some funny idling, even stalling until you drive the car a bit.

MR.T

Sorry, didn't notice the link you embedded.

My reading tells me to start the car with no accessories running and hold the revs at 3k until the radiator fans kick on. Then let it idle for 5 mins.