Primary O2 sensor
 

Where is the primary O2 sensor and the secondary O2 sensor...
Thanks

TTT

Re: Primary O2 sensor
 

Primary O2 sensor is on the exhaust manifold, secondary O2 is immediately after the catalytic converter or sometimes on the cat itself...

BDC is right........if you're thinking of hooking up an A/F ratio gauge, it should be tapped on the primary O2 sensor (white wire).

naw, Its just that the check engine light is on and when I checked it it was the primary O2 sensor.

have u reset the ECU? your car is not that old. my car did that for a while causing a code1 CEL. it's gone now and all i did was removed the sensor and washed it off with a hot soapy water. i've been running without a CEL for 3 months now ;)