Where is the oxygen sensor VW Jetta 2003?

Answer 1

There are three oxygen sensors (to my knowledge) on a VW Jetta 2003 2.0L. There are two on the exhaust near the catalytic converter, a pre-cat sensor, and a post-cat sensor. The post cat is easily visible right after the catalytic converter. The pre-cat is a little trickier, but again, if you take off the heat guard it's right on the exhaust manifold right before the cat. And the third is the secondary air injection sensor. I haven't been able to directly locate it, and there is not much info on the net about it. But I assume it's somewhere right around the air pump, which on the 2.0L is in the front of the engine compartment between the engine and the electric fan. Hope this helps.