Oxygen sensors generally do not operate when "cold". Engine is in open loop mode while warming up. In additionl, oxygen sensors generally do not cause this kind of problem. I've read elsewhere that there is a sensor in the distributor that can get dirty and cause the symptoms you're experiencing. Sorry, don't have any links handy.
The oxygen sensors are in the exhaust pipes on most models.
There are two.
There are two.
The signs and symptoms for oxygen toxicity include changes in vision, nausea, twitching, and dizziness. More serious symptoms can include seizures and possible death.
O2 sensors are always located on the exhaust system.
I wasn't aware that there was a middle oxygen sensor. I have a 1997 Villager that was vandalized and the catalytic converter and O2 sensors were stolen. From what my mechanic tells me and Auto Zone there are only 2 sensors, one in front of the catalytic converter and one behind it.
Abnormally slow breathing is a symptom of oxygen toxicity
possible symptoms are the engine warning light will be on
Your Villager has only one O2 sensor located on the front catalytic pipe before the converter. You should be able to look down between the engine and radiator and see it.
Both oxygen sensors are in the exhaust pipe, one under the front of the engine, one roughly under the passenger seat are.
Death.
There are two, on in front of the converters near the engine, and one after the converters, roughly under the passenger seat.