S&T Series Blazer, Bravada, Envoy, Jimmy, Rainier, Trailblazer, Xtreme

Fuel Trim Diagnostics


In order to meet OBD II regulations, fuel trim information is displayed on a Scan Tool in percentages. This is different from the way fuel trim has been traditionally displayed on a Scan Tool. Short term and long term fuel trim functions within OBD II are similar to past usage, only their measurement units will differ. The fault detection logic and MIL operation is the same as that described for Misfire Diagnosis.

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Fig. Fuel Trim Conversion Graphic