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Vehicle Emissions Inspection and Maintenance (I/M): Policy, Guidance and Test Procedures

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Policy guidance on inspection and maintenance (I/M) program implementation.

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Inspection and Maintenance (I/M) Procedures

The IM240 Transient I/M Dynamometer Driving Schedule and The Composite I/M Test Procedure (PDF) (EPA-AA-TSS-91-1, 18pp, 154K, January 1991)

IM240 Technical Guidance

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Acceleration Simulation Modes (ASM)

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