Ask the Mechanic: Do hybrid cars use electricity to accelerate?

Hello John, hybrid cars use their electric motors during starts, take off and overtaking because the electric motor provides more torque or force needed to instantaneously accelerate the car in the direction where its headed. The benefit of the hybrid motor during acceleration at starts and during overtaking is to improve torque, efficiency and economy.

Hybrid electric vehicles are driven by petrol internal combustion engines and one or two electric motors which draw energy from batteries. Hybrid batteries are charged by regenerative braking and the petrol internal combustion engine. The primary propulsion system of a hybrid car is the petrol driven internal combustion engine. The petrol engine propels the car when driving in slow traffic or regular driving.

CAN ENGINE VALVES CAUSE HIGH FUEL CONSUMPTION?

Hello Paul, lately, my Spacio’s fuel consumption has been high. After inspection, my mechanic says the engine requires some repairs, especially the valves. Is it recommendable to repair engines?

Ebenezer.

Hello Ebenezar, reduced engine power and fuel economy can be caused by dirty engine air intake valves with crust-like carbon deposits as a result of combustive acids. This dirt sponges on the fuel passing by the intake system. Dirty valves do not sit or close appropriately. This affects the air fuel ratio and subsequently, the efficient burning of fuel. Fuel system cleaning additives in some fuels can help to keep the intake valves clean. In case of valve damage from severe dirt buildup a mechanic can replace them after determining that they cannot be cleaned.

MY CAR’S AC TAKE LONG TO COOL

Hello Paul, when I start my car air conditioning, it takes a long time to cool down. What could be the problem?

Margaret

Hello Margaret, car air conditioning should take a short time to cool the car down when you start it. When your car air conditioning or AC takes long to cool the car, it could be one of the following causes; a weak or ageing AC compressor pump, low AC coolant or gas pressure or a dirty AC cabin filter.

An ageing or faulty AC compressor is weak and takes longer to build up sufficient AC pressure. Therefore, you need to rev the engine faster for a little while before the compressor can build enough pressure to cool the car cabin. Low refrigerant coolant pressure will take long to cool your car. Normal AC pressure should be approximately 14-15 bars in most cars.  If it is half of that or less, then cooling the car will take longer.

To resolve this problem, ask an AC technician to test the AC system for pressure leaks and refill the gas to the recommended pressure. A dirty AC cabin filter will reduce your AC system’s cooling efficiency. An AC cabin filter is designed to trap dirt or pollen in the ventilation system of a car. When it becomes blocked, it restricts air in flow and reduces efficiency of cool air. Access the AC cabin filter and replace it if found dirty.

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