Unless it’s a trick of the photo angle, the side electrode of the plug on the left appears bent, and the gap completely closed. That’s probably the source of your misfire.
Try a fresh spark plug and very, very gently clean the threads in the head.

 

You are absolutely correct, the electrode is bent and completely closed. How could that happen?

 

IMO the risk of future seizing is increased if there has been thread damage, it needs professional clean up (capable Indy or Porsche).
Best of Luck.

 

I can't say I inspected the plugs before they went in. I put a bore scope in and looked at the top of the pistons, no evidence of any contact with the plug. The plugs are the right ones and exactly match the ones that came out (both in model # and length). Can't imagine you could over-thread a plug to the point a piston comes in contact (unless they are not the right length).

I am going to gently chase the threads and re-install the old plugs (which are in very good shape), then cross every part of my body and hope it runs well and no CEL. Will update here once I do so for future readers. If it does not run right it will go onto a flatbed to a shop.

 

I can't say I inspected the plugs before they went in. I put a bore scope in and looked at the top of the pistons, no evidence of any contact with the plug. The plugs are the right ones and exactly match the ones that came out (both in model # and length). Can't imagine you could over-thread a plug to the point a piston comes in contact (unless they are not the right length).

I am going to gently chase the threads and re-install the old plugs (which are in very good shape), then cross every part of my body and hope it runs well and no CEL. Will update here once I do so for future readers. If it does not run right it will go onto a flatbed to a shop.

My guess is that the plugs were damaged upon receipt. I've hard a few plugs over the years that had been dropped prior to delivery and came to me out of spec. I've even had plugs shipped to me along with other parts and every plug was out of its box and bouncing around loose in the box. It would be nice if the plugs were shrink wrapped upon boxing at the factory but that would add a few pennies to their cost and lessen the profit margin.

 

Cleaning out the threads properly is a good idea and easy to do, but make sure you get a proper thread cleaning tap. They are not the same as regular taps. A regular thread tap is designed to remove material to cut new threads. You don't want to do that. You just want to clean debris out from the existing threads.

 

Indeed, ordered several M12 1.25 thread chasers to see which one I feel is best. Very difficult due to the depth and small diameter of the plug receptacle.

 

Quick update and some good news. It took me quite a while to put the plugs back in going slow and backing out then in many times. I had to use a little PBlaster on the plug threads to get one in cleanly without significant resistance (will clean out the threads when I receive the chasers I ordered). Put the coils back on and started her up. Running like it should. Still have a check engine light on, does anyone know if this needs cleared or if it would go away if there is no issue?

 

If you triggered a misfire fault code (chk eng light), it’ll require reading & clearing with a scanner.

 

In the future to prevent galling of the threads, when removing if any resistance is felt simply reverse direction a few times while removing instead of forcing it in one direction. This allows any debris to be cleared free instead of piling up and causing galling. Also always inspect plugs thoroughly and check gap before installing and compare the length of nose and electrodes beside the original plugs. A hint of anti-seize wouldn't hurt either upon installing once you get the threads chased and cleaned up. Hopefully no metal flecks are in the cylinder.

 

No anti-seize should be put on the metal part of the spark plug per Porsche. The only place anti-seize is recommended is on the ceramic part of the plug to facilitate the coil plug going on smoothly.

 

Thankfully all is well. Use my iCarsoft code reader to read then clear codes. After running it no CEL and runs as good as new (maybe a bit quicker with the new APR coils. Thanks for the input.

 

glad to hear it.
As a long time DIY’er, I know the sickening feeling of, “Oh no, what have I done?”

 

In addition to the bent electrode the base of the electrode looks funky. I also would not trust that plug after bending the electrode back into position. Replace at least that one. Be aware there are counterfeits so buy only from reputable sellers.

 

I wouldn't even consider using that plug. New ones on the way from FCP Euro.

 

FWIW, jury rig some 1/4in (6mm?) tube to your favorite vacuum device to extract debris...metallic chips in a cylinder risk scoring the wall.

 

FWIW, jury rig some 1/4in (6mm?) tube to your favorite vacuum device to extract debris...metallic chips in a cylinder risk scoring the wall.

Yes

...
Plus whenever you have issue like that, I recommend to use vacuum cleaner on the open spark plug holes to suck out potential leftover debris from the cross thread before you put the new sparks in.

 

glad you got it sorted.

Cross threaded sparkplug threads are nightmare fuel

 

glad you got it sorted.

Cross threaded sparkplug threads are nightmare fuel

As a fellow DIY’er I’d say WHEW, but that seems to be quite an understatement!! Glad you got it sorted out.