1.1 This test method is commonly referred to as the Sequence VG test² and has been correlated with vehicles used in stop-and-go service prior to 1996, particularly with regard to sludge and varnish formation.³ It is one of the test methods required to evaluate oils intended to satisfy the API SL performance category.

1.2 The values stated in SI units are to be regarded as standard.

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Specific hazard statements are given in 7.7, 7.10.2.2, 8.3.4.2, 8.4.4.3, 9.2.6, 9.3.4.5, 12.1.1.7, 12.2.1.4, and Annex A1.

1.4 A Table of Contents follows:

	Section
Scope	1
Referenced Documents	2
ASTM Standards	2.1
SAE Standards	3.2.3
ANSI Standard	2.2
Terminology	3
Definitions	3.1
Definitions of Terms Specific to This Standard	3.2
Summary of Test Method	4
Significance and Use	5
Apparatus-General Description	6
Apparatus-The Test Engine	7
Sequence VG Test Engine	7.1
Required New Engine Parts	7.2
Reusable Engine Parts	7.3
Specially Fabricated Engine Parts	7.4
Special Engine Measurement and Assembly Equipment	7.5
Miscellaneous Engine Components-Preparation	7.6
Solvents and Cleaners Required	7.7
Assembling the Test Engine-Preparations	7.8
Assembling the Test Engine-Installations	7.9
Engine Installation on the Test Stand	7.10
Engine Fluids-Supply/Discharge Systems	8
Intake Air	8.1
Fuel and Fuel System	8.2
Engine Oil and Engine Oil System	8.3
Coolants	8.4
Measurement Instrumentation	9
Temperatures	9.1
Pressures	9.2
Flow Rates	9.3
Fuel Consumption	9.4
Speed and Load	9.5
Exhaust Gas	9.6
Humidity	9.7
Miscellaneous Laboratory Equipment	10
Test Stand Calibration	11
Test Procedure	12
Pre-Test Procedure	12.1
Engine Operating Procedure	12.2
Periodic Measurements and Functions	12.3
Special Maintenance Procedures	12.4
Diagnostic Data Review	12.5
End of Test Procedure	12.6
Interpretation of Test Results	13
Parts Rating Area-Environment	13.1
Sludge Ratings	13.2
Varnish Ratings	13.3
Clogging	13.4
Sticking	13.5
Used Oil Analyses	13.6
Assessment of Test Validity	14
General	14.1
Average Exhaust Gas NOx Levels	13.1.5
Used Oil Analyses-Interpretation	14.2
Blowby Flow Rate	14.3
Manifold Absolute Pressure	14.4
Fuel Consumption Rate	14.5
Oil Consumption	14.6
Engine Parts Replacement	14.7
Quality Index and Deviation Percentage	14.8
Final Test Report	15
Report Forms	15.1
Photographs	15.2
Precision and Bias	16
Keywords	17
ANNEXES
Safety Precautions	Annex A1
Control and Data Acquisition Requirements	Annex A2
Detailed Specifications and Photographs of Apparatus	Annex A3
Special Service Tools for the Test Engine	Annex A4
Test Engine Part Number Listing	Annex A5
External Oil Heat Exchanger Cleaning Technique	Annex A6
Sequence VG Report Forms and Data Dictionary	Annex A7
Dipstick Calibration	Annex A8
Critical Part Supplier List	Annex A9
Operational Data Log-Engine Oil	Annex A10
Rating Worksheets	Annex A11
Fuel Injector Flow Measurements	Annex A12
APPENDIXES
Piston and Ring Measurements Record Forms	Appendix X1
Sources of Materials and Information	Appendix X2
Description of Scott Quarterly Gas Audit Service	Appendix X3