Page 249 - Understanding Automotive Electronics
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7 DIGITAL ENGINE CONTROL SYSTEM
Figure 7.6
Closed-Loop Correction Factor
The computer detects this condition by reading the throttle angle
sensor voltage. High throttle angle corresponds to heavy engine load and is
an indication that heavy acceleration is called for by the driver. In some
vehicles a switch is provided to detect wide open throttle. The fuel system
controller responds by increasing the pulse duration of the fuel injector signal
for the duration of the heavy load. This enrichment enables the engine to
operate with a torque greater than that allowed when emissions and fuel
236 UNDERSTANDING AUTOMOTIVE ELECTRONICS
