General characteristics of wheel suspensions
The suspension of modern vehicles need to satisfy a number of requirements whose aims partly conflict because of different operating conditions (loaded/ unloaded, acceleration/braking, level/uneven road, straight running/cornering). The forces…
Flywheel energy storage
Flywheel energy storage systems for use in vehicle propulsion has reached application in the light tram vehicle. They have also featured in pilot-production vehicles such as the Chrysler Patriot hybrid-drive…
Improvements in electronic engine control
The digital engine control system in this chapter has been made possible by a rapid evolution of the state of technology. Some of this technology has been briefly mentioned in…
Summary of control modes
Engine crank (start) The following list is a summary of the engine operations in the engine crank (starting) mode. Here, the primary control concern is reliable engine start. 1. Engine…
System diagnosis
Another important feature of microcomputer engine control systems is their ability to diagnose failures in their control systems and alert the operator. Sensor and actuator failures or mis-adjustments can be…
Automatic system adjustment
Another important feature of microcomputer engine control systems is their ability to be programmed to adapt to parameter changes. Many control systems use this feature to enable the computer to…
Evaporative emissions canister purge
During engine-off conditions, the fuel stored in the fuel system tends to evaporate into the atmosphere. To reduce these HC emissions, the fuel tank is sealed and evaporative gases are…
Closed-loop ignition timing
The ignition system described in the foregoing section is an open-loop system. The major disadvantage of open loop control is that it cannot automatically compensate for mechanical changes in the…
Electronic ignition control
An engine must be provided with fuel and air in correct proportions and the means to ignite this mixture in the form of an electric spark. Before the development of…
EGR control
A second electronic engine control subsystem is the control of exhaust gas that is recirculated back to the intake manifold. Under normal operating conditions, engine cylinder temperatures can reach more…
