Integrator and Block Learn Values
TEST DESCRIPTIONIf a problem occurs in the fuel metering system, it usually results in either a rich or lean exhaust condition. This condition is sensed by the oxygen sensor and causes the Electronic Control Module (ECM) to change the fuel calculation (injector pulse width). The change made to the fuel calculation will be indicated by a change in the integrator and block learn values, which can be monitored by a "SCAN" tool. A short term change to the fuel calculation is indicated by the integrator value, while a long term change is indicated by the block learn value. Average integrator and block learn values will be around 128, but may vary slightly from engine to engine.
For "SCAN" tester diagnosis refer to Computers and Controls / System Diagnosis / Procedures / Scan Tester Diagnosis. Testing and Inspection