calibrated position if it has lost its reference count.
Idle Speed Flag (Forward / Reverse)
This will indicate the stepper motor direction for idle control. A FORWARD
reading should indicate a lower idle and less airflow, a REVERSE reading
should represent a higher idle and more airflow.
Injector Pulse (mS)
Range: 0 to 1002 mS
Fuel injector pulse width is a measurement of how long the injector is
held open to control fuel flow. Displayed in milliseconds. A higher reading
indicates that the injector is staying open longer and that more fuel is
being injected per pulse. Injector Pulse also serves as the right injector
pulse width on systems with a right and left bank.
Integrator or Short Term Fuel Trim
Range: 0 to 255
An indication of fuel delivery made by the ECM during a closed loop
operation. The integrator adds or subtracts fuel, being constantly adjusted
by the oxygen sensor signal. When the exhaust shows an ideal 14.7 to 1
air-fuel mixture, no integrator action is needed and the reading should be
128. If the exhaust is lean, the integrator adds fuel and the reading
increases. If the exhaust is rich, the integrator subtracts fuel and the
reading decreases. The integrator is a short term fuel compensator which
works in conjunction with Block Learn. Also see Block Learn.
ISC Throttle Switch (Open / Closed)
This parameter indicates if the throttle is at idle where idle speed control
should be active. If the ECM has detected an idle condition, this
parameter should indicate CLOSED. In all other open throttle situations,
this parameter should indicate OPEN.
Knock Sensor
Range: 0 to 255
Knock activity noted by the ECM. When the value reaches the maximum
of 255, it jumps back to 0 and continues counting upward. It provides an
indication of knock and that a resultant timing adjustment has been made.
If the number is increasing during Monitor Mode, then knock is occurring.
On some engines the value will reset with each correction made.
Knock Retard (Degrees)
Range: 0 to 90°
A reading of timing retard that the ECM sends to the ignition module when
engine vibration is detected by a knock sensor. Displayed in crankshaft
degrees of retard to be subtracted from total timing.
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Summary of Contents for EX-SCAN 5000
Page 1: ...USERS MANUAL...
Page 95: ...NOTES Page 95...
Page 96: ...NOTES Page 96...
Page 97: ...NOTES Page 97...
