2000 S70 - rough idle/misfire

[dvlchd3]

Hi all,

My car has a rough idle and runs rough when warm (at operating temperature). It is inconsistent, some drives are fine (I have a 70mi drive to work, 90% highway), some exhibit the rough idle issue.

I previously replaced the front O2 sensor (by advice of trouble code). This seemed to resolve the issue for a while, but it came back a few months later (could be a different issue, but same symptoms).

I also confirmed there are no leaks in the vacuum tubes (by smoke machine).

The front O2 trouble code is gone now, but I now have 2 more.

Here are the current CEL codes:
P0300 - General misfire (same before O2 replacement)
P1672 - camshaft reset valve (new)
P0442 - leak diagnostic - minor leak (new - I assume unrelated)

The last two are new since the mechanic did work, and may be the result of a 12 year old car with ~200k miles. I guess I'll start by replacing the reset valve, would this cause a rough idle? If not, any suggestions on what else to check?

[regent]

The misfire may point to ignition components. How old are your plugs and coils?

[dvlchd3]

That was my first thought as well, however, I would've expected specific cylinders to be misfiring if it were the coils/plugs.

I will check them out when I go to replace the camshaft reset valve (while praying this is the only issue).