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Code 44 - Lean Exhaust Indication

Code 44 indicates that the ECM has seen oxygen sensor voltage under the following conditions:

  1. A fixed dwell of under 10° indicates the problem is still present. A fixed dwell under 10° at idle, with dwell varying at 3000 RPM, usually indicates an intake leak. Check this area prior to replacing oxygen sensor.
  2. This test checks if the ECM is able to respond to a rich condition caused by choking the engine. If it does, the problem is a lean engine condition, NOT ELECTRICAL.
  3. If dwell increases to over 50° with heavy choking, the fault is an air leak. If air is going to exhaust ports, disconnect the solenoid(s) for the air control valve. If air still goes to the ports, air valve is faulty.
  4. This step puts a rich oxygen sensor signal (about 1 volt) into term. "9" of the ECM. Dwell should increase (lean command).
Fig 1: Code 44, Lean Exhaust Indication
G10258
Fig 2: Code 44, Lean Exhaust Indication
GB0048265