[yogi_123rd]

Dave you are going about diagnosing the problem the wrong way (hit or miss replacement of parts). Firstly, your gas mileage indicates a problem. It should be 22-23 mpg range.
When the computer detects a problem in one of its sensors, it sets a fault code and usually lights the check engine light. It can also puts itself into "limp" mode if the problem is bad enough where it will make guesses based on the other working sensors for the bad sensor it can't read. This is good in that it will keep the engine running, but bad in that it usually results in too much gas usage and poor engine performance.

First obtain the fault codes in the computer. Turn the ignition switch on-off-on-off-on-off-on (three times without starting car) and count the flashes of the check engine light. Each code is a two digit code, each flashing digit is seperated by a pause. The end of the list of codes is 55.

If you have another problem that results in too much gas going in, then expect the code for the oxygen sensor too to be set as a side effect of the real problem.
Next, to get the meaning of the codes, do a web search for sites with them listed, using the keywords - "Chrysler computer codes". This is a good starting point.