A faulty O2 sensor can cause the symptoms described. Here are the procedures for diagnosing the peoblem
Code 13 = Open Oxygen Sensor Circuit.
When exhaust temperature is less than 600 F (316 C), the O2 sensor is open and produces no voltage. An open sensor circuit or cold sensor will not all system to entire closed loop.
NOTE: Test numbers refer to test numbers on diagnostic chart.
1. Code 13 will set at normal operating temperature if at least 2 minutes have passed since engine start, Code 21 or 22 is not present, O2 signal voltage is steady at.35-.55 volt and throttle position sensor signal is greater than idle. All conditions must be met for at least 1 minute.
2. This determines if fault is in O2 sensor, ECM or wiring.
3. Use only a high-impedance Digital Volt-Ohmmeter (DVOM) while checking for continuity in signal and ground circuits. If ground circuit is open, voltage on signal circuit will be greater than.6 volt.
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Friday, January 7th, 2011 AT 3:53 PM