A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
W
X
Y
Z
Knocking
Knocking is a phenomenon that occurs in a gasoline engine if the fuel used does not have a high enough octane rating. Knocking is essentially combustion at the wrong time. It gets its name from the pinging or knocking noise that it makes. More importantly, it results in lower fuel efficiency and hotter engine temperatures, and it can lead to engine damage over time.