Car that runs on air

This engine was developed between the end of 2001 and the beginning of 2002. It uses an innovative system to control the movement of the 2nd generation pistons and one single crankshaft. The pistons work in two stages: one motor stage and one intermediate stage of compression/expansion.The engine has 4 two-stage pistons, i.e. 8 compression and/or expansion chambers. They have two functions: to compress ambient air and refill the storage tanks; and to make successive expansions (reheating air with ambient thermal energy) thereby approaching isothermic expansion. Its steering-wheel is equipped with a 5kW electric moto-alternator. This motor is simultaneously:
*the motor to compress air
*the starting motor
*the alternator for recharging the battery
*an electric moderator/brake
*a temporary power supply (e.g. for parking) No clutch is necessary.

The engine is idle when the car is stationary and the vehicle is started by the magnetic plate which re-engages the compressed air. Parking manoeuvres are powered by the electric motor.The CAT´s 34 P04 engine is equipped with patented variable-volume butts and a dynamic variable-volume volumetric reducer.

I'll believe it when I see it.

If it runs on hot air it should get better mileage in Washington than anywhere else.