Spark plugs and misfires

[RUNCDO87]

This week has been a big week for my Fiesta. I did the backup camera Forscan mod, added sound deadening to the floors, doors, and rear hatch, installed a K&N air filter, fixed a blend door actuator, installed a COBB Stage 1 tune, and changed the spark plugs to step colder plugs (NGK). After a bit of a scare regarding possibly dropping a piece of insulator into the cylinder, I started the engine only to notice a significant misfire at low idle. The strange part was there was no CEL. I removed the tune and reinstalled the original spark plugs but the misfire was still there. After fiddling around in FORSCAN, I reset all of the control modules and I found that cylinder 1 was misfiring significantly and there was a misfire count on cylinder 3 (not the cylinder with the broken plug). I reseated the coil and plug and tried again. But to no avail, the misfire still exists. Also have some issue with the brake lights but that seems unrelated. Is there something I am overlooking? I know that sometimes the engine needs to learn am I not giving it enough time to fix itself? I only let it idle for maybe 30 seconds to a minute because I am afraid I am going to destroy something.

TLDR; changed a bunch of stuff and a misfire formed.

 

[MagnetiseST]

Are you sure you didn't drop ANY of the insulator into the cylinder? I did this and ended up needing an engine...

 

[RUNCDO87]

Are you sure you didn't drop ANY of the insulator into the cylinder? I did this and ended up needing an engine...

I vacuumed it out and boroscoped it and didn't see anything. It's possible something was in there but I'm not well versed enough to know if the misfire can be linked to damage in a different cylinder.

 

[TyphoonFiST]

Change back to Stock tune* See if misfire goes away. Then get back to us with some data. BTW I wouldn't Run a Cobb file if my FiST depended on it. Also did you use anti-seize on the plugs? Did you Torque the spark plugs to 13 ft lbs?

 

[Sam4]

That was a hell of a list!! No matter what tuners say, I am convinced that 95% of us will never be able to use colder plugs, and will notice misfires and slower (harder?) starts. Like a "miracle of motors" Honda SI, except to get at the HP you need to be in the 5000+ RPM range, albeit we need to get at least to 3.....just saying normal range NGKs will perform as designed.

 

[M0LTEN]

A compression check would give you an idea of the cylinder condition.
That would at least give you some peace of mind that the misfire isn't from low
compression.
Still it sounds like an electrical issue, make sure the gaps on the plugs looks good
possibly a damaged plug.

 

[XR650R]

You don't need colder plugs. Go back to stock.