<P> The motor in Civic hybrid is about a quarter - inch (6.4 mm) thicker than that of the Insight . Through improvements to the magnetic coils of the DC brushless motor, it achieves 30 percent greater assisting and regenerative torque than the previous model without increasing the size . </P> <P> It generates more torque (46 versus 36 pound - feet) than the motor in Insight . The electricity is stored in a battery consisting of 120 1.2 - volt Ni - MH D - cells wired in series . The battery can charge and discharge more rapidly and efficiently though the total capacity is reduced from the Insight's (6.0 versus 6.5 AH). Efficiency of the battery modules is increased, through a reduction in energy losses . The battery is housed with the electrical controller in a package called the Intelligent Power Unit (IPU). The new packaging reduces the size of the system by 50 percent and allows the IMA equipment be placed behind the rear seat in the trunk . The unit weighs only 63 lb (29 kg) and is one - third smaller than that of the Insight . </P> <P> The two spark plugs in each cylinder can fire either sequentially or simultaneously, enabling more efficient burning during lean - burn mode and more often lean - burn operation . The engine can operate at a lean 22: 1 air - to - fuel ratio more than 60 percent of the time on a flat road . The VTEC cylinder idling system of the engine closes the valves in three of the four cylinders when the car is decelerating, reduces the power lost to the engine by 50 percent, and allows the IMA to extract more electrical energy during braking . The rocker arms operating the intake and exhaust valves have two modes: valve - lift mode or idle mode . They are engaged via a synchronizing piston . During deceleration, the synchro piston disengages the lift - mode rocker arm so that the valves remain at rest, effectively sealing off the cylinder . </P> <P> An idle stop feature shuts off the engine automatically when stopped, then restarts immediately when the driver removes their foot from the brake . This auto idle stop system contributes to both greater fuel efficiency and lower emissions . During stop and go driving, the engine will turn off when the car comes to a stop for the first time, however, if the car does not go above 10 mph (16 km / h) and stops again, the engine will not turn off unless the car is stopped for more than 15 seconds . </P>

How many spark plugs in a honda civic hybrid