the old converter was rattling like the guts were out. Replaced with after market converter and muffler. Tech reinstalled the original sensor and everything seemed fine. Later that day engine light came on and jeep ran rough. Does the sensor need to be replaced?

 

What year is the truck?

 

97

 

You need to figure out what the code is before you start throwing sensors at it.

 

Well I'm pretty sure you're talking about a truck with OBDII. If you don't have a code scanner you'll have to go to an Autozone, or other auto parts place and a lot of them will scan it for you for free.

Once you have the error codes post the results and someone can help you

 

it is probably reading it as too rich cause the cat takes a few days to break in...about 100 miles. just pull the negative battery cable off the battery for 30 sec and then put it back on. the code will disappear and it should stop doing it after a 100 mile break in period.

 

Yup yup 96 started obd2 , but some earlier cars,trucks,and jeeps can have the codes read from a real good scan tool.(Thats 1995 and ealier.)