P0174 and valve noise?

[Sonnick]

So Sunday morning I start my car and notice 'valve noise' (I think?) I have a video that I will post later. Sounds like valve tick, but goes away once the car is warmed up and doesn't happen while driving. However, a CEL ensues as well as surging RPMs. What I mean by this, is while shifting gears, the RPMs stay up until my foot is completely off the clutch pedal. Also, when I put the car in neutral to coast, the RPMs stay up for 3-5 seconds, then drop down.

The next morning the CEL is still there as is the valve noise. Once warmed up again, it's gone. I drove about 80 miles (was with my GF in Maine for the weekend) and the CEL stays on, yet the surging RPMs go away. Drove about another 15 miles and the CEL goes away. Got the code checked and it was P0174. I read there are a few different causes for this: vacuum leak, O2 sensor, (my front PCD may be leaking), clogged injector, etc.

Does anyone have any suggestions? My car has just over 101K on it and is still on the stock TBelt with no valve adjustment thus far. I'm putting these on my to-do-list ASAP btw. Just changed the plugs and the front were white, pointing to running lean. I think I'm going to start by replacing the front PCD with my buddy and seeing if that keeps the code away. Could it be as simple as that? Thanks for any help.

If my memory serves correct, the code also said "Front bank lean - cyl 2." Does that make sense? Or could I have confused that with bank 2? I've also had a code reoccur for some time now, yet hadn't gotten it checked (stupid I know). I'm assuming it is this one. I've also been getting pretty poor gas mileage. When the plugs were done it got a little better, but I still feel it should be better. Thanks again.

[Sonnick]

So I had a leaking front downpipe. We replaced that as well as my failed motor mounts. Car feels much smoother and planted. I got a new CEL yesterday when I replaced my intake filter, but it has since gone away. I ran the diagnostic test and it came back with nothing, so I'm assuming it went away. However, I am going to reset the ECU tonight by unplugging the (-) terminal for awhile and see what happens.

Here is a video of the noise it was making. Btw, it made the same noise Saturday, but other than that it has not come back. I believe it has something to do with the colder weather.

http://s32.beta.photobucket.com/user..._0495.mp4.html

[Sonnick]

No one? I was really hoping Fredsvt would post in here...

[Sonnick]

No one? I included a video as well. Is this something I should be worried about?

[Sonnick]

92 views.....could it be the oil? I just got my oil changed before my road trip and the next day it happened upon cold startup. I checked the dipstick and it was perfect, but they did use synthetic. I'm not sure what kind/weight though.