Introduced in late 1991, trims available in the hatchback body style in the U.S. and Canada were the CX, VX, DX (EH2 models) and Si (EH3), however the VX and Si models were discontinued in Canada after model year 1993, while the DX was discontinued after 1994 (leaving only the base CX model).
With a total interior room (passenger and luggage) of 90 cu.ft.,
the hatchback was classified by EPA of U.S. as subcompact.

CX: The economical CX was the base model equipped with all-manual features, and power brakes.
In the U.S., it came with the 8-valve 70 hp (52 kW) 1.5L D15B8 engine and manual transmission.
With 42/48 miles per gallon (mpg) (city/hwy) [revised to 2008 EPA rating: 35/43 mpg city/hwy] or 40/47 mpg (city/hwy) [revised to 2008 EPA rating: 33/42 mpg city/hwy], the CX was the second most fuel-efficient Civic model of the fifth generation, after the VX.
CX models in Canada came with the same 16-valve 102 hp 1.5L D15B7 engine as in the DX -model, but could also be ordered with automatic transmission which also came with power steering.
The 1995 CDM CX models (sometimes colloquially referred to as the "CX-Plus") added the rear wiper/washer as a standard feature, and could be ordered with side mouldings and manual passenger-side mirror.

VX: During the late 1980s, and the early 1990s, as a result of high gasoline prices, and the consumer demand for relief, automobile companies, particularly Toyota, and Honda competed to see who could field the most fuel efficient production automobile.
The Civic VX was Honda's entry for 1992.

Fitted with the same manual transmission as the USDM CX, the VX was identical to the base model CX except that it gained improved fuel efficiency from various weight reduction methods such as reduced trim and molding, VX model-specific lightweight 13" aluminum alloy wheels, 165/70/R13 tires, and through a 92 hp (69 kW) 1.5 L (D15Z1) VTEC-E engine.
These features on the VX yielded 48/55 mpg (city/hwy) [revised to 2008 EPA rating: 39/49 mpg city/hwy] or 44/51 mpg (city/hwy) [revised to 2008 EPA rating: 36/46 mpg city/hwy]  
The D15Z1 engine's efficiency was enhanced by placing cam followers(bearings) at every cam lobe, to reduce friction, the use of only two piston rings per cylinder, to reduce friction, and the ability to burn an ultra lean(for the time) fuel air mixture at idle, and below 2500 rpm at low load.
 This was achieved by only opening one valve during the intake stroke, rather than both, below 2500 rpm engine speed, placing the multiport fuel injectors very near the intake valves, and by using an ultra sensitive oxygen (lambda) sensor.
The oxygen sensor is mounted on the cast iron exhaust manifold, to be as close to the cylinders as possible, so the sensor will be as hot as possible for more accurate readings.
It has two O2 measurement electrochemical cells, rather than the single cell that at the time was universal.
This same model sensor has been adopted by racing teams to monitor the combustion in each cylinder of racing engines during the tuning process, one per cylinder, because of its sensitivity.

The opening of only one intake valve below 2,500 RPM results in much more of the pressure drop between atmospheric pressure, and the inside of the cylinder to be across the valve than would otherwise be the case.
This results in an exceptionally turbulent flow, very good mixing of the charge, very high speed flame propagation at ignition, high resistance to predetonation (knock), and very low amounts of unburned hydrocarbons, and carbon monoxide, and increased engine torque, and power in both lean burn mode, and at more normal fuel-air mixtures, below 2,500 rpm.
As a result of, the increased torque, and power at low rpm, the engine's torque, and power curves are between those of normally aspirated gasoline, and diesel engines.
Since the VX has what was for the time an ultra low coefficient of aerodynamic drag of 0.30 cd, the car could operate at highway speeds in lean burn mode.

The D15Z1 engine was considered revolutionary for its day.
To this day, the VX remains a favorite of Hypermilers.

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Introduced in late 1991, trims available in the hatchback body style in the U.S. and Canada were the CX, VX, DX (EH2 models) and Si (EH3), however the VX and Si models were discontinued in Canada after model year 1993, while the DX was discontinued after 1994 (leaving only the base CX model). With a total interior room (passenger and luggage) of 90 cu.ft., the hatchback was classified by EPA of U.S. as subcompact.
CX: The economical CX was the base model equipped with all-manual features, and power brakes. In the U.S., it came with the 8-valve 70 hp (52 kW) 1.5L D15B8 engine and manual transmission. With 42/48 miles per gallon (mpg) (city/hwy) [revised to 2008 EPA rating: 35/43 mpg city/hwy] or 40/47 mpg (city/hwy) [revised to 2008 EPA rating: 33/42 mpg city/hwy], the CX was the second most fuel-efficient Civic model of the fifth generation, after the VX. CX models in Canada came with the same 16-valve 102 hp 1.5L D15B7 engine as in the DX -model, but could also be ordered with automatic transmission which also came with power steering. The 1995 CDM CX models (sometimes colloquially referred to as the "CX-Plus") added the rear wiper/washer as a standard feature, and could be ordered with side mouldings and manual passenger-side mirror.
VX: During the late 1980s, and the early 1990s, as a result of high gasoline prices, and the consumer demand for relief, automobile companies, particularly Toyota, and Honda competed to see who could field the most fuel efficient production automobile. The Civic VX was Honda's entry for 1992.
Fitted with the same manual transmission as the USDM CX, the VX was identical to the base model CX except that it gained improved fuel efficiency from various weight reduction methods such as reduced trim and molding, VX model-specific lightweight 13" aluminum alloy wheels, 165/70/R13 tires, and through a 92 hp (69 kW) 1.5 L (D15Z1) VTEC-E engine. These features on the VX yielded 48/55 mpg (city/hwy) [revised to 2008 EPA rating: 39/49 mpg city/hwy] or 44/51 mpg (city/hwy) [revised to 2008 EPA rating: 36/46 mpg city/hwy]  
The D15Z1 engine's efficiency was enhanced by placing cam followers(bearings) at every cam lobe, to reduce friction, the use of only two piston rings per cylinder, to reduce friction, and the ability to burn an ultra lean(for the time) fuel air mixture at idle, and below 2500 rpm at low load.  This was achieved by only opening one valve during the intake stroke, rather than both, below 2500 rpm engine speed, placing the multiport fuel injectors very near the intake valves, and by using an ultra sensitive oxygen (lambda) sensor. The oxygen sensor is mounted on the cast iron exhaust manifold, to be as close to the cylinders as possible, so the sensor will be as hot as possible for more accurate readings. It has two O2 measurement electrochemical cells, rather than the single cell that at the time was universal. This same model sensor has been adopted by racing teams to monitor the combustion in each cylinder of racing engines during the tuning process, one per cylinder, because of its sensitivity.
The opening of only one intake valve below 2,500 RPM results in much more of the pressure drop between atmospheric pressure, and the inside of the cylinder to be across the valve than would otherwise be the case. This results in an exceptionally turbulent flow, very good mixing of the charge, very high speed flame propagation at ignition, high resistance to predetonation (knock), and very low amounts of unburned hydrocarbons, and carbon monoxide, and increased engine torque, and power in both lean burn mode, and at more normal fuel-air mixtures, below 2,500 rpm. As a result of, the increased torque, and power at low rpm, the engine's torque, and power curves are between those of normally aspirated gasoline, and diesel engines. Since the VX has what was for the time an ultra low coefficient of aerodynamic drag of 0.30 cd, the car could operate at highway speeds in lean burn mode.
The D15Z1 engine was considered revolutionary for its day. To this day, the VX remains a favorite of Hypermilers.
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Honda Civic (fifth generation)