EGR / EVAP Data
Engine Speed - Range 0-16384 RPMEngine Speed is computed by the PCM from the fuel control reference input. It should remain close to desired idle under various engine loads with the engine idling.
Desired Idle - Range 0-3187 RPM
The idle speed that is commanded by the PCM. The PCM will compensate for various engine loads to keep the engine at the desired idle speed.
ECT - Range -40°C- 215°C (-40°F- 419°F)
The Engine Coolant Temperature (ECT) sensor sends engine temperature information to the PCM. The PCM supplies 5 volts to the engine coolant temperature sensor circuit. The sensor is a thermistor which changes internal resistance as temperature changes. When the sensor is cold (internal resistance high), the PCM monitors a high voltage which it interprets as a cold engine. As the sensor warms (internal resistance decreases), the voltage signal will decrease and the PCM will interpret the lower voltage as a warm engine.
IAT - Range -40°C- 215°C (-40°F - 419°F)
The PCM converts the resistance of the Intake Air Temperature (IAT) sensor to degrees in the same manner as the ECT sensor. Intake air temp is used by the PCM to adjust fuel delivery and spark timing according to incoming air density.
MAP - Range 11-105 kPa, 0-5.0 Volts
The Manifold Absolute Pressure (MAP) sensor measures the change in the intake manifold pressure which results from engine load and speed changes. As the intake manifold pressure increases, the air density in the intake also increases and additional fuel is required.
BARO - Range 11-105 kPa, 0-5.0 Volts
The Barometric Pressure (BARO) sensor measures the change in the intake manifold pressure which results from altitude changes. This value is updated at ignition "ON" and also at Wide Open Throttle (WOT).
TP Sensor - Range 0-5.0 Volts
The Throttle Position (TP) sensor is used by the PCM to determine the amount of throttle demanded by the operator of the vehicle. The TP sensor will read between 0.36-0.96 volt at idle to above 4 volts at Wide Open Throttle (WOT).
TP Angle - Range 0-100%
Throttle Position (TP) angle is computed by the PCM from the TP sensor voltage input. TP angle will auto zero to 0% at idle (TP voltage below 0.90 volt) and read 100% at Wide Open throttle (WOT).
O2S 1 - Range 0 - 1132 mV
The Oxygen Sensor (O2S 1) represents the exhaust oxygen sensor output voltage. This voltage will fluctuate constantly within a range between 100 mV (lean exhaust) to 900 mV (rich exhaust) when operating in "Closed Loop".
HO2S 2 - Range 0 - 1132 mV
The Rear Heated Oxygen Sensor (HO2S 2) represents the exhaust oxygen output voltage beyond the catalytic converter. This voltage will remain inactive or appear lazy within a range of 100 mV (lean exhaust) and 900 mV (rich exhaust) when the system is operating in "Closed Loop".
IAC Position - Range 0-255 Counts:
The scan tool displays the PCM command for the Idle Air Control (IAC) pintle position in counts. The higher the number of counts, the greater the commanded idle speed reads. The Idle Air Control responds to changes in the engine load in order to maintain the desired idle RPM.
Fuel Trim Cell - Range 0 - 22
Fuel Trim Cell is dependent upon engine speed and MAP sensor readings. A plot of RPM vs. MAP is broken down into 22 cells. Fuel Trim Cell indicates which cell is currently active.
Short Term FT - Range 0-255 (-100% to 100%)
Short Term Fuel Trim (FT) represents a short term correction to fuel delivery by the PCM in response to the amount of time the oxygen sensor voltage spends above or below the 450 mV threshold. If the oxygen sensor has mainly been below 450 mV, indicating a lean air/fuel mixture, short term fuel trim will increase to tell the PCM to add fuel. If the oxygen sensor voltage stays mainly above the threshold, the PCM will reduce fuel delivery to compensate for the indicated rich condition.
Long Term FT Range 0-255 (-100% to 100%)
Long Term Fuel Trim (FT) is derived from the short term fuel trim value and is used for long term correction of fuel delivery. A value of 128 counts (0%) indicates that fuel delivery requires no compensation to maintain a 14.7:1 air/fuel ratio. A value below 128 counts means that the fuel system is too rich and fuel delivery is being reduced (decreased injector pulse width). A value above 128 counts indicates that a lean condition exists and the PCM is compensating
Decel EWMA - Range -10 to 10 kPa:
The Exponentially Weighted Moving Average (EWMA) is an average kPa difference between the expected MAP kPa change the PCM expected to see when the diagnostic ran and the actual MAP kPa change that was seen. The EGR EWMA value should always be near -3. Whenever the EGA EWMA value becomes more positive (towards 0), then the EGR system is becoming restricted.
Desired EGR Position - Range 0 to 100%:
The desired EGR position is the commanded EGR position. The PCM calculates the desired EGR position. The higher the percentage, the longer the PCM is commanding the EGR valve ON.
EGR Actual - Range 0 to 100%:
The PCM monitors the results of its commands through a feedback signal. The EGR valve sends a voltage signal back to the PCM. The signal represents the actual EGR pintle position. The EGR pintle position should remain close to the desired EGR position.
Delta MAP Change - Range -20 to 20 kPa:
The amount of MAP change the PCM sensed from the beginning of the diagnostic until the end. Used to calculate the difference in the actual MAP change and the expected MAP change to determine the Decel EWMA value.
EGR Decel Trip Sample Counter - Range 0 to 255 Counts:
Displays the number of test that have been run for DTC P0401. Once the counter reaches 255, the number will stop until a battery disconnect or an EGR DTC has been cleared.
EVAP Solenoid - Range 0%/-100%:
When energized, the EVAP Solenoid allows the fuel vapor to flow from the EVAP canister to the engine. The EVAP Solenoid is normally closed. The EVAP solenoid is pulse width modulated by the PCM. The EVAP Solenoid reads 0% when closed to 100% when fully opened.
EVAP Vent Solenoid - Range ON/OFF:
The EVAP Vent Solenoid allows fresh outside air to the EVAP canister during purge mode. The EVAP vent Solenoid allows the diagnostic to pull a vacuum on the fuel tank by closing the vent solenoid.
Fuel Level Sensor Range - 0%-/-100%:
The Fuel Level Sensor monitors the fuel level in the tank. The fuel level sensor monitors the rate of change of the air pressure in the EVAP System. Several of the Enhanced EVAP System diagnostics are dependent upon the correct fuel level.
Fuel Tank Pressure - Range 0.0-5.0 Volts:
The fuel tank pressure sensor measures the difference between the pressure or the vacuum in the fuel tank and the outside air pressure. When the air pressure in the fuel tank equals the outside air pressure, the output voltage of the sensor is 1.3 to 1.7 volts.
Output Driver 1 - Range SHRT00000000
Open00000000 (binary display)
Output Driver Modules (ODMs) are used to allow various systems to function by providing a ground circuit. The scan tool will display "Os" in each of the 8 positions when the circuitry is OK. If a "1" appears in any of the positions, then either a short or open circuit is being detected.
Output Driver 2 - Range SHRT00000000
Open00000000 (binary display)
Output Driver Modules (ODMs) are used to allow various systems to function by providing a ground circuit. The scan tool will display "Os" in each of the 8 positions when the circuitry is OK. If a "1" appears in any of the positions, then either a short or open circuit is being detected.
Engine Run Time - Range 0:00:00-18:12:15 hours:minutes:seconds:
The engine run time is a measure of how long the engine has been running. When the engine stops running, the timer resets to zero.
Number of Current DTCs - Range 0-255:
Indicates the total number of current Diagnostic Trouble Codes (DTC's) set. Does not necessarily mean the Malfunction Indicator Lamp (MIL) is illuminated.