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Home >> Chevrolet >> 1999 >> Express 1 Ton Van V8-5.7L VIN R >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Testing and Inspection >> Scan Tool Testing and Procedures >> Scan Tool Data, Normal Values and Definitions >> Scan Tool Data Definitions - Powertrain Systems >> Loop Status
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Loop Status

(Open Loop/Close Loop)
The Loop Status indicates when the VCM is controlling fuel delivery which is calculated using the HO2S bank 1 and 2 inputs. This is called closed loop fuel control. During open loop, the VCM ignores the HO2S input and bases fuel delivery upon TP, engine coolant, and MAF sensor input.
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