I have a 1996 Stratus 2.4L with a pretty new bright Check Engine light. The OBD code reader tells me that P0135 means that the Upstream O2 sensor is faulty. I am having a heck of a time locating it, (I think it is on the back side of the exhaust manifold). Has anyone had experience with this problem?

How do I get to the thing if that is the right sensor?

 

yes, that's the right one. best bet is to get an 02 sensor remover. looks like a norm socket with a slot down one side for the wire to pass through. before starting soak everything with liquid wrench, it helps. do this the night before, 2-3 times a 1/2 hr apart (on a cold motor!). next mourning pop off the heat shield and the 02 sensor should be a bit easier to get at. good luck.