Thread: Plugs burnt/bent and 27* knock!

if you had bent plugs then more then likely your pistons are chipped or something got in there i would also do a compression test to see what psi's look like
burnt plugs mean it got real lean and real hot

This could be a simple vacuum hose. Typically they won't show up as a code etc until it's a huge leak. I agree with Wicked about the plugs. it's not good.

Being at 17 AFR when coasting is completely normal. When you are on the throttle, that's when it would be bad.