Originally Posted by fmertz

Been dealing with a P1646 for a bit now. I read it to be passenger side upstream sensor heating circuit. Checked the electrical manual. Swapped the heater relays in the hope the fault code would move to the driver side. No such luck. Ended up buying a _wideband_ Denso sensor 234-9029 on eBay. Not super cheap, so I changed only one. Figured there was some "life" left on the other one.

Finally got around to swapping it out this week end. Removed the intake elbow for more room. First checked the sensor plug to make sure it was the same. Check. Removed the sensor (with the help of a cheap HF crows foot O2 sensor socket) with a 3/8" breaker bar and a extension pipe. Check. Put the new sensor in, with the supplied copper grease applied to the treads. Snaked the wire back in, plugged in the harness and re-attached the plug on its post. Check. Put the intake elbow back in, making sure it was sitting low, and not touching the hood lining.

Then moved on to the battery and did a "hard reset" to make sure the computer would forget whatever baseline data off of the old faulty sensor and start anew. Then I reset the OBD fault codes and did a test drive a bit later. Car is now with a P1000, with some monitors pending, as expected.

Altogether, a quick and easy job as I was lucky enough not to have to fight the sensor off the manifold.

PS: Car now reads code P1111, all monitors completed. Happy car makes for a happy owner.

Originally Posted by MRomanik

I made a tonneau cover for the useless back seats.
Cost of materials ( marine grade vinyl,foam padding,canvas snaps, foam board) about $45.