Misfire/Lean-out issue

So I recently decided to spice up my life and buy a 2007 MS3, but I have a problem.
I'm experiencing misfires at idle, and it will throw a code for random misfires and cylinder specific misfires after a driving cycle.(I also believe I have a vacuum leak) The Car will pull all-the-way till Sunday and drives fine, but it just misfires at idle.(Also smokes a lot likely b/c of clogged cats) I bought it from a buddy who replaced the PCV right before he sold it to me. We did a compression test and all cylinders are in spec. (175 170 165 175) It no longer seems to be burning oil after the PCV replacement, so thats good. I thought that maybe fuel had something to do with it so I pulled the plugs and coils, and from left the right plugs 1&3 looked good while 2&4 looked like they were leaning out.(But no leanout code) It was misfiring on 2 so I swapped the coils between 2&3 to see if that was causing a problem and the misfire jumped to 1? So then I switched coils 1&4 and the misfire stayed on 1. I decided to pull off the intake manifold and fuel rail to see if the stock injector seals had failed and if the valves were clogged with carbon build up. Long story short, I found no seals and It looked like Cyl 4 had some leaked fuel in the injector port. Got some seals coming in to solve that problem and I'm also cleaning the injectors/ports/valves to see if this will solve the problem. If this doesn't work I'm worried it could be bad injectors on 2 and 4, or maybe bad valves? All the other forums I've looked at don't have posts about this issue so I'm hoping I can find my answers here.

Thanks

 

Install new plugs and gap them properly. Fix the clogged cat issue as well. I would've done that prior to digging into the fuel system.

 

Forgot to mention that new plugs were installed with the pcv,(previous cylinder 2 plugs electrode was all messed up) I checked and the new plugs are gapped correctly. They are also the correct ngks. I need to swap the plugs to make sure that its the cylinders and not the plugs (I should have done that before I tore the car apart), downpipe+internals is definitely next.

 

Check this
Also clean your spill valve. HERE
These will be good to check off the list. Also check your ground wire for your coil harness to make sure it is in good shape.

 

I haven't had the whining noise from the prv thankfully. Though the clip had been broken/missing from the return line attached to it, and the fitting was held on by zip-ties (oof) Thinking about getting used line w/ clips from ebay to replace that. Also, thanks for pointing me in the direction of the spill valve and grounding wire, something definitely to look into.

 

Corksport injector seals for sure. Get injectors cleaned professionally for sure.

 

Got the seals, and soaked injectors in b12chemtool and got a lot of gunk off. What would be a good place to get them cleaned/flow-tested? Also ordered a return line w/ both clips and on the hunt for a 32mm wrench to crack that spill valve loose.

 

Your pic doesn't work.
I got a 32mm from a local farm and tractor place. You can send them to https://www.injectorrx.com/ they are pretty popular. I think Freek tune might also do them. This is also a good kit for the orings and such but still use the CS or Overspeed seals. https://www.rockauto.com/en/moreinfo.php?pk=10338116&cc=1434570&jsn=918

 

What would be the appropriate site to host pics on? Also totally in sync on the GB seals got box full of them sitting next to the injectors.

 

I used imgur it's pretty easy. I just have an album setup for this stuff and then paste the direct link so the picture shows.

 

You can upload em here.

 

Thanks
Update: just checked the plugs again and found that they were actually gapped to .025", now they are at .028" plugs were also NGK's 1-step colder (LTR7IX-11)
Here's a pic, 1-4 from left to right:

 

Injectors are on their way to Texas, and with my new giant wrench I was able to remove the spill vlave to clean it. I also did the "spring stretch mod" for the coils.

 

Check your spark plugs for cracks in the ceramic as well.

 

Plugs are all good. The new fuel line and coolant arrived today too. Now I'm just waiting on injectors and I can get the car running again.

 

So I'm in the process of putting the car back together and having trouble reinstalling the green clip fuel line. I've looked at some pictures online and it seems that the blue clip line is supposed to go on the farther back pipe and the green clip line is supposed to go on the front. Is this correct?

 

Like this.

 

You should not have to take the clips off fully, and one the lines are seated you just snap them back in.

 

Yup, they were on incorrectly. Got that sorted out as well as a bunch of other issues. Car is slowly coming back together.

 

Welp, I got the car back together and cranked her up. Everything seemed fine till I realized fuel was spraying everywhere. The fuel rail has pushed itself off of the injectors and pulled the remaining threads out with the bolts, not good. We're going to attempt to fix the lack of treads with a Heli-Coil.

Brightside: No misfires in the 20-30 seconds it was running.