you mean plugs?
you need to take the intake off to get to the back three plugs...
Unburnt carbon
NO!
there is no timing when you change the spark plugs the car adjusts itself
How do I change spark plugs in 2009 Toyota Corolla? whaT TOOLS I NEED
no
You won't need a diagram if you change one spark plug wire at a time.
yes
You need to remove the valve cover ((V8) motor) and remove the spark plug coils, then you can change the plugs.
Your sparkplug won't spark means that is too old already and it is worn out or it was wet or something and you need to change that one.
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Yes, if the spark plug wires can be connected to the distributor and works.