So I've read some Threads here but nothing seemed to answer my question so maybe you can help.

I was running my car hard all day today just for the heck of it and my check engine light came on. The car idles rougher all of a sudden too. I went to Autozone to have the codes pulled and it was P0021 Camshaft Position. I've also been fighting a P0300 Misfire Code on top of that which came up again yay. Anyways

I just got an 17* timing advance about a week ago and also replaced the front 3 coils with some used OEM ones from an org. member to try and help out with the P0300 code. I feel like the car runs a little different from the start with the 17* timing, almost seems like I lost power in the higher RMP range.. Should I switch back to 15* timing? or buy a new sensor? I think it would be Bank 2 from what I've read.

 

Lets start from the top,

P0021 or p0011 are usually set on these cars due to low oil. Also, when engine is running low on oil you will hear and feel an engine running rough. You will hear the timing chain rattle as well.
First and foremost, check and add engine oil. Your engine is most likely burning oil.

As far as P0300 is concerned, if you are not getting any other codes associated with the misfire (i.e. p0301, p0302, etc) your issue is not any specific coil or spark plug at any individual cylinder but a part that all cylinders share like a vacuum leak, mass air flow sensor, ecu, etc. I had a random misfire code on an 04 maxima that I found to have a faulty ecu, runs well after replacing the computer.

You might need to do a bit more diagnostic to pinpoint your problem.

 

Well I just checked my oil yesterday and it was a little above the halfway mark so I don't think that could be the problem and I've only got about 1500 miles since last oil change. My car does burn a little oil from piston rings where they are probably wearing out.

For the p0300 code these are the things I've done..

Cleaned MAF, New OEM spark plugs, 6th gen rear valve cover w/PCV and gasket, New vacumm hoses, seafoam cleaned, Lucas fuel injector cleaned, 3 front OEM coils..

So what step could i take toward fixing the p0021 code, as far as the p0300 code, I've been dealing with this for over a year so I donno. lol