DTC 44

Fig. 80 - Chart #44 Diagnosis:

Code 44 indicates one of the following faults has been detected;

a. Oxygen sensor voltage lower than specified
b. Closed Loop
c. Above a specified TPS value
d. For a time longer than specified

1. Check to see if the condition is still present. 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 these areas prior to replacing the O2 sensor.
2. Checks 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.
3. 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. If air still goes to the ports, it is a faulty valve.
4. This step puts a rich O2 signal (about 1 volt) into Terminal "9" of the ECM. Dwell should increase (lean command).