A gas-sensing misfire detection system is being installed in the latest Aston Martin, the DB7 Vantage, to ensure the maximum efficiency of its engine.
The V12 six litre, 420bhp engine includes a Visteon electronic engine management system (EMS) which monitors and records performance within each of the engine’s 12 cylinders.
At the DB7’s maximum speed of 185mph the system monitors 42,000 signals from within the combustion chambers every minute.
Performance within each of the chambers is measured by an electrical signal from the spark plugs. When the engine is running these emit an ignition spark of over 20,000V.
This is immediately followed by a second 40V charge crossing the spark plug gap to confirm the presence of ionised gas, a by-product of successful combustion. Ionised gas is an electrical conductor and its presence completes a circuit which sends a signal back to the EMS’s computer indicating successful combustion.
The EMS analyses each combustion cycle for misfires or deterioration in an individual cylinder’s performance. If there is a spark misfire or other ignition fault then fuel flow to the affected cylinder can be altered instantaneously to reduce harmful emissions.
Aston Martin developed the system in conjunction with Cosworth and the Ford Research and Vehicle Technology Group.