O2 Sensor

What are the symptoms of a bad 02 sensor? Is it difficult to replace?
Thanks

------------------
1984 Targa

on my car, the main symptoms were a very subtle but annoying pulsing and hesitation in lower rpms under acceleration. once i changed the o2 sensor, the problem went away. others have mentioned that a faulty o2 sensor can cause erratic idling or excessively rich or lean running conditions. i believe the bentley manual lists it as a maintenance item that should be changed every 60,000 miles. see the 'o2 sensor necessary?' and 'more o2 sensor stuff...' threads from a couple weeks back... they've got lots of info in them, including detailed definition of what the sensor does.

it's pretty easy to change, assuming the last o2 sensor installed on your car had some antiseize applied to the threads! because of the intense heat, these things can get pretty ornery when trying to remove them...

if you remove your driver's side rear tire, you'll see a sensor with 3 wires attached sticking out of your catalytic converter (or test pipe, if you don't have a cat...); that's the o2 sensor. you can use a 22mm wrench to remove it; just be ready to use some serious force if it's stuck...

unfortunately, the sensors cost about $230 if you get them from the porsche dealer. the good news is, though, you can use any bosch 3 wire o2 sensor as a replacement. you just simply cut off the connector and solder/heatshrink to the connector wires already in your car. i bought one from a ford, i believe, and it cost me $50. well worth the savings.

by the way, thanks to everyone on this bbs who helped educate me on this o2 sensor stuff!!!!!!!

------------------

Adam Nitti
www.adamnitti.com
'85 Carrera
'74 3.0 CS

Be careful....they weld themselves and will often time pull threads....soak liberally with rust penetrant as you remove it...sometimes this doesn't work either...good luck jer