just took out my spark plugs to check my gap the gap is all good but i looked at my cylinders with my snap own camera thingy borascope...cylinder 123 have alot of carbon build up and cylinder 4 has next to nothing for carbon on the top is this normal???

 

what is your mods on the car

 

1 clean cylinder can sometimes mean a coolant leak into that cylinder (which is cleaning it)

seen it before 1st hand.

Not sayin thats whats goin on in ur case.

could be an uneven fuel/airflow thing too.

 

i looked saw no craks...only mods are a CAI and exhaust

 

such an incredible tool; butchered

 

i love it it has helped me out so much at work i just had a brain fart when i was typing it here lol