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2004 996 C2 Secondary Air Injection System/ Trans Cooler Question


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My 2004 C2 Cab has me stumped with regards to how a slow warm up due to Tiptronic coolant valve failure will affect the emissions system and O2 sensor readings. I have a CEL P0131 and I have a new O2 sensor (sensor 1, bank 1). I have read that extended warm up can cause the O2 sensor to throw a code. I have determined that the trans cooler control valve has a blown diaphragm so that will affect the secondary air system and create a vacuum leak while the change over valve is open. My durametric also confirms that my readiness of the secondary air system has failed - all other emission systems say ready. My question is will the trans cooler being in the default open position substantially affect engine warm up and therefore also contribute to the O2 sensor reading improperly and taking too long for signal to reach the ECU? Does the secondary air injection system have anything to do with introducing additional air into the intake system? Thanks

Edited by Chris Altmeyer
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P0131 Oxygen sensor upstream
NOTE:
The fault "Over limit value" is detected if the oxygen sensor voltage is > 1.5 V for an uninterrupted period of more than 5 s.


Diagnostic conditions
- DME control module power supply 10.5 V … 16 V
- Oxygen sensor heater switched on for > 70 s
- Oxygen sensing active
- Exhaust temperature 600 °C (1,112 °F)... 750 °C (1,382 °F)
- min. 3 s overrun
- No secondary air injection or diagnosis of secondary air system active
- No tank ventilation or diagnosis of tank ventilation system active
- No other oxygen-sensor faults stored


Possible fault causes
- Fault in oxygen sensor heater A If this exists, is to be taken care of first
- Loose contact or corrosion in the connector
- Short circuit to B+/ground/between wires or open circuit in the wiring
- Heater injection
- Oxygen sensor faulty
- DME control module faulty

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