Minimum Function System

Fig. 021 - Chart - Code 44 Lean Exhaust Indication.:

1. Check to see if the condition is still present. A fixed dwell of under 15° indicates the problem is still present. A fixed dwell under 15° at idle with it varying dwell at 3000 RPM usually indicates an intake leak. Check these areas prior to replacing the O2 sensor.
2. Check to see 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.
2a. If dwell increases to over 50° with heavy choking, the fault is an air leak since the ECM was able to respond. If air is going to exhaust ports, disconnect the solenoid(s) for the air control valve.
3. This step puts a rich O2 signal (about 1 volt) into Terminal "3" of the ECM. Dwell should increase (lean command).