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The best way to compare fuel economy is the highway fuel economy number. It will correlate to real-world highway driving pretty well. If you want to get another good comparison measure, compare the curb weight of the vehicles you are considering. The lighter vehicle can be expected to use less fuel, handle better, and be easier on tires and brakes. Weight is the enemy of everything a vehicle must do: accelerate, brake, turn.
Just drive but take it easy with acceleration until the coolant gets warm (usually 5 minutes). If you are driving a manual transmission, try to keep the rpm below 3000 rpm until the coolant is at normal operating temp.
Dave
Every high voltage electric line and connector in a high voltage hybrid is bright orange to warn you. All of the full-Hybrid cars from GM, Ford, Hyundai, Toyota, Honda, and VW/Audi have battery high-voltage systems over 200 volts.
These high voltage wires and connectors are high quality and robust and shouldn’t be a hazard by themselves. If you do have to work on any of the high voltage components, the first thing you do is disconnect the big orange connector at the battery pack and this de-energizes the rest of the system. I would not recommend anyone work on a hybrid repair project without first reading and understanding the factory shop manual. The factories have special training for the technicians in their dealerships for working with the high-voltage systems.
Dave
No, there are basically 3 types of full-hybrids. The Toyota system is known as Power-Split where the “transmission” contains 2 electric motors (that are also operable as generators) that are connected to each other and the gasoline engine’s output by differential gears. This transmission has not clutches or shifting mechanisms. All of the variability in overall gear ratio between the engine and the wheels is controlled by the power controller that varies what each electric motor/generator does. This system also controls whether the the electric motors add power to the output of the gasoline engine or take power to charge the batteries.
The Hyundai and VW/Audi systems are the popular “P2” systems which are simply adding a large electric motor between the engine and the gearbox. This motor is in place of the engine flywheel and can be de-clutched from either the engine (to drive the car electrically) or from the engine (to regeneratively charge the batteries on deceleration.
The Honda system is unique. The transmission has an electric generator that is connected to the gasoline engine a motor/generator that is connected to the transmission output. At low to moderate speeds, only the output electric motor drives the car and the power comes from the battery. The battery can be charged by the other generator or form the motor generator on decels. In this mode the car is a series hybrid; no direct connection between the engine and the drive axles. Above roughly 40 MPH, their is a clutch that can lock-up and connect the engine directly to the final drive with an overall gear ratio equivalent to top-gear. In this mode the wheels can be driven by any combination of engine power and electric power. Here is a schematic: https://www.caranddriver.com/features/a15114066/explaining-the-honda-accords-shrewdly-designed-new-hybrid-system-tech-dept/
Yes, if your new car has the feature to calculate the oil change intervals, this is a better measure of when to change your oil than just miles driven or time since last oil change. On a modern Mazda, this would be the Maintenance Monitor, and could be set to “Flexible”. The true oil life is a function of how many hours the engine has been running and the temperature history of the oil. A good oil life system could have you change your oil in as little as 1500 miles if you do nothing but short trips in a cold climate, or more than 10,000 miles if you do mostly highway driving without getting stuck in traffic.
