LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Chevrolet >> 2004 >> Optra Base, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - 1.8L (L79) - Diagnostic Information And Procedures >> Scan Tool Data List
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Scan Tool Data List

The Engine Scan Tool Data List contains all engine related parameters that are available on the scan tool. The list is arranged in alphabetical order. A parameter may appear in any one of the data lists, and in some cases may appear more than once, or in more than one data list in order to group certain related parameters together.

Use the Engine Scan Tool Data List only after the following conditions are determined:

Scan tool values from an engine that is operating correctly may be used for comparison with the engine you are diagnosing. The Engine Scan Tool Data List represents the values that would be seen on a normal operating engine.

IMPORTANT: Do not use a scan tool that displays faulty data. The scan tool concern should be reported to the manufacturer. Use of a faulty scan tool may result in misdiagnosis and unnecessary parts replacement.

Only the parameters listed below are referenced in this service information for use in diagnosis. If all values are within the typical range described below, refer to Intermittent Conditions for diagnosis.

The column labeled Data List indicates where a parameter is located on the scan tool. Review the scan tool operating manual for the exact locations of the data lists. The following is a description of each term listed:

All

The Parameter is in all data lists indicated below.

Eng

Engine Data

EGR

EGR Data

EVAP

EVAP Data

FT

Fuel Trim Data

HO2S

O2S/HO2S Data

MF

Misfire Data

CH

Cooling/HVAC Data

IPC

IPC Data

FF

Freeze Frame Data

FR

Failure Records Data

Scan Tool Data List

Scan Tool Parameter Data List Parameter Range/Units Typical Data Values
Engine Idling/Radiator Hose Hot/Park or Neutral/Closed Loop/Accessories Off
5 Volt Reference 1 EGR, EVAP, CH 0-5 Volts 5.0 Volts
A/C High Side Pressure Sensor CH 0-5 Volts Varies
A/C High Side Pressure Sensor CH kPa/psi Varies
A/C Relay Command Eng, EGR, MF, CH On/Off Off
A/C Request Signal CH Yes/No No
Air Flow Calculated Eng, FT, HO2S, MF, FF, FR g/s 3-6 g/s
Air Fuel Ratio Eng, FT, HO2S, FF, FR Ratio 14.7:1
BARO Eng, EGR, EVAP, HO2S, FT, FF, FR, MF 65-104 kPa Varies with altitude
Catalytic Converter Protection Active HO2S, FT, MF Yes/No No
CMP Active Counter Eng, MF 1-3 Counts Varies
Coolant Hot Lamp (If Equipped) IPC On/Off Off
Decel. Fuel Cutoff EGR, FT, HO2S Active/Inactive Inactive
Desired EGR Position EGR % Varies
Desired IAC Position Eng Counts Varies
Desired Idle Speed Eng, EVAP, FF, FR 0-7,000 RPM 800-950 RPM
ECT Sensor Eng, EGR, EVAP, FT, HO2S, MF, CH, IPC, FF, FR -39°C to +140°C (-38°F to +284°F) Varies
EGR Flow Test Count EGR Counts Varies
EGR Learned Minimum EGR Volts Varies
EGR Position Sensor Eng, EGR, FT, MF % Varies
EGR Position Sensor EGR Volts Varies
EGR Position Variance EGR Counts Varies
EGR Solenoid Command EGR % Varies
Engine Load Eng, EGR, EVAP, FT, HO2S, MF, CH, FF, FR 0-99% 25-40% - Idle
25-40% - 2500 RPM
Engine Run Time ALL 0:00:00 Varies
Engine Speed ALL RPM 750-950 RPM
EVAP Purge Solenoid Command (If Equipped) Eng, EVAP, FT, HO2S 0-100% Varies
EVAP Vent Solenoid Command (If Equipped) Eng, EVAP Venting/Not Venting Venting
Fail Counter FF, FR Counts Varies
Fans High Speed CH ON/OFF Varies
Fans Low Speed CH ON/OFF Varies
Fuel Level to Cluster EVAP, IPC % Varies
Fuel Level Sensor Eng, EVAP, FT, IPC 0-5 Volts Varies
Fuel Level Sensor Eng, EVAP, FT, IPC % Varies
Fuel Pump Relay Command Eng, FT On/Off On
Fuel Tank Pressure Sensor (If Equipped) Eng, EVAP in H2O/mm Hg Varies
Fuel Tank Pressure Sensor (If Equipped) Eng, EVAP, FF, FR 0-5 Volts Varies
Fuel Trim Cell Eng, FT, FF, FR Cell Number 20?
Fuel Trim Learn Eng, FT, FF, FR Enabled/Disabled Enabled
O2S/HO2S 1 Eng, EVAP, FT, HO2S, FF, FR 0-1,006 mV Varies 400-800 mV
O2S/HO2S 1 Ready HO2S Yes/No Yes
O2S/HO2S 2 Eng, EVAP, FT, HO2S, FF, FR 0-1,006 mV Varies 400-800 mV
IAC Position Eng, EGR, FT, HO2S, CH, FF, FR Counts 15-40 Counts
IAT Sensor Eng, EGR, EVAP, FT, HO2S, MF, CH, FF, FR -39° to +140°C (-38° to +284°F) Varies
Ignition 1 Signal Eng, EGR, EVAP, FT, HO2S, MF, CH, IPC Volts 12.0-14.5 Volts
IMT Valve Command (If Equipped) Eng On/Off Off
Injector PWM Eng, FT, HO2S, MF, FF, FR 0-9 ms 4.6-5.4 ms
Knock Retard Eng, EGR, CH Degrees Varies
KS Active Counter Eng Counts Varies
Long Term FT Eng, EVAP, FT, HO2S, FT, FF, FR -100% to +100% 0%
Long Term FT Avg. FT -100% to +100% 0%
Loop Status Eng, EVAP, FT, HO2S, FF, FR Open Loop/Closed Loop Closed Loop
Low Fuel Lamp Command (If Equipped) IPC On/Off Off
MAP Sensor Eng, EGR, EVAP, FT, HO2S, MF, FF, FR kPa 38-50 kPa
Varies with Altitude
MAP Sensor Eng, MF, FF, FR 0-5 Volts 0.9-1.7 Volts
MIL Command Eng, IPC On/Off Off
Mileage Since First Failure FF, FR km - miles Varies
Mileage Since Last Failure FF, FR km - miles Varies
Misfire Current Cyl. 1-4 MF 0-255 Counts 0
Misfire History Cyl. 1-4 MF 0-65,535 Counts 0
Not Run Counter FF, FR Counts Varies
Pass Counter FF, FR Counts Varies
PNP Switch Eng, EGR, IPC Park/Neutral/In Gear Park/Neutral
Power Enrichment FT, HO2S, MF, FF, FR Active/Inactive Inactive
Power Steering Switch (If Equipped) Eng, CH High Pressure/Normal Pressure Normal Pressure
Rich/Lean to Lean/Rich Ratio Sensor 1 FT, HO2S Counts Varies
Rich/Lean Transition Sensor 1 FT, HO2S Counts Varies
Rough Road Sensor (If Equipped) MF 0-5 Volts 2-3 Volts
Short Term FT Avg. FT -25% to +25% -3% to +3%
Short Term FT Eng, EVAP, FT, HO2S, FF, FR -25% to +25% -3% to +3%
Spark Eng, FT, HO2S, MF, CH -20 to +40 Degrees 2-10 Degrees
Start Up ECT EVAP, HO2S, CH, FF, FR -39° to +140°C (-38° to +284°F) Varies
Start Up IAT EVAP, HO2S, CH, FF, FR -39° to +140°C (-38° to +284°F) Varies
SVS Lamp Command (If Equipped) IPC On/Off Off
TCC Enable Solenoid Command (If Equipped) Eng, MF On/Off Off
Total Fuel Trim Average EVAP, FT, HO2S -100 to +100% Varies
Total Misfire MF Counts 0
TP Sensor Eng, EGR, EVAP, FT, HO2S, MF, FF, FR 0-5 Volts 0.0-0.3 Volts
TP Sensor Eng, EGR, EVAP, FT, HO2S, MF, FF, FR % 5-15 %
TWC Temperature Calculated MF Temperature Varies
Vehicle Security Status (If Equipped) Eng, IPC Fuel Enabled/Fuel Disabled Disabled
Vehicle Speed Sensor Eng, EGR, EVAP, FT, HO2S, MF, CH, IPC, FF, FR Km/h
mph
0 km/h
(0 mph)