First off I know there are tons of threads regarding the p0326. The problem is I cant seem to find an answer for my problem. For starters I have an 05 MCS with a 15% pulley and 1 step colder plugs. I got the car with 40k miles now at 62k and it has always made a very faint rattling noise under load intermittently. Recently I have noticed a little bit of shaking under load, not so much that the whole car shakes but enough that if I let go of the wheel i can see it shake a little more under acceleration. Last week my service engine light came on, no EML and no noticeable difference in performance. A few days later it turned off. I refilled a couple days ago and added a bottle of lucas fuel system cleaner. The next day the light turned on again. Still no power loss. Are there different codes for engine knock vs knock sensor failure or anyway to know if I have an engine problem or a knock sensor problem?



Thank you for your help

 

I had the same issue with my 2005 s at about 60k miles. I think it was the same code. it was just the sensor not performing. I was worried about the same thing. I believe it mainly just detects pinging from poor fuel. I had mine replaced and all was good. It is a cheap part but it is not easy to get to on the s.

 

Im gonna order up the part and the stuff needed for the supercharger oil change. Does anyone know of anything else I should check /replace while I have the front end off and supercharger removed???

 

I paid to have the knock sensor done, although I do most work myself normally. My mini guy did it, but he did make the comment that the knock sensor needs to be torqued to spec as it is sensitive. So... just make sure to use a torque wrench on it.

 

SES light turned off again a few days ago. I pulled the plugs and did a compression test. the plugs have about 10k on them they don't look bad to me. looking through the plug hole the pistons look very dirty. They almost look rusted but there is no water in the oil or any other signs of a blown gasket. The compression test looked good to me. 130, 120, 125, and 125. the numbers seem low but within 10 psi so I don't think there is a problem. I'm going to run a bottle of lucas octane booster and see if that gets rid of the noise. Does anyone know of a good source to buy a JCW head? If I can get a good price I might change out the head while I have the supercharger off.

 

couldn't figure out how to put all 4 pics in 1 post

 

The ping or knock sensor goes on the front. I have not seen too many of these go bad. But it happens.



Ping Sensor part # 12141487246


http://www.ecstuning.com/Search/SiteSearch/12141487246/



Thanks

 

I think I have figured out most of my problems. I typically use chevron gas. The two times the SES light came on I was not using Chevron. One time was 76 and I think the other was shell. Now that I'm only using Chevron the light hasn't came back on. after a few tanks of chevron and no lights I threw in a bottle of Lucas octane booster. It all but got rid of the nock. I'm happy the nock is gone but it's ridiculous that I should have to add octane booster to a stock tune. does anyone know of any mechanical issues that could be causing my problem? I was thinking cat or excessive exhaust back pressure but that should throw a code if its not working properly????