How can the Chrysler Town & Country instantaneously calculate its fuel consumption?
You can find some pretty cool stuff if you do patent searches on http://www.uspto.gov for Chrysler’s patents. The Town & Country can calculate its fuel consumption very easily in two ways. First, it knows the injector pulse width and the fuel rail pressure is regulated to approximately 50 PSI, and therefore it can determine precisely how much fuel has been injected into the engine. Second, it can use manifold pressure and engine RPM along with factors like engine displacement to determine how much fuel is consumed because under normal operating conditions the amount of fuel burned is in proper stoichiometric ratio with ambient air. For example, with the 3.8L engine on a 60F (15C) day, the calculation boils down to: Fuel gallons per hour (GPH) = engine speed (RPM) / 9000 * absolute manifold pressure (inHg) For example, if you are idling at 700 rpm and have 7 inHg of absolute manifold pressure (approximately 23 inHg vacuum at sea level), with this equation you would be able to estimate t
