I just recently swapped out my injectors in my cherokee 4.0, did the whole reset thing with touching the battery cables, turn on ignition, lights on then off. Seems to start really great, runs great, then the check engine light comes on after a little while when driving it and seems to idle a little rough. If I turn it off then start it back up, the light will be out and will idle perfect. I drive around for a bit and the same thing happens. My question is will this clear up or has anyone else had this problem with the injector upgrade/swap?

 

I believe you need to give time for the computer to adjust. Keep driving and see if it improves.

 

Which injectors did you install?

 

Here is a pic with the number. It only runs like this when it is up to temp but when I turn it off then start it right back up, the light is out and will come back on after about a mile or so and do the same thing. I have read that this one will work in my motor. What do you all think? Will it go away in time?

 

If your light comes on it should throw a code I would find out what your engine thinks the problem is.

 

Wrong injector, flowing too much fuel.
Best is the 710 (last 3 digits)
Here is a comprehensive chart.
http://www.fuelinjector.citymaker.co...low_Rates.html

 

What year XJ do you have also.

My bad, could have asked that the first time.

The following are what should be used on each year of XJ 4.0:

87-90 - 280155746
91-98 - 280155703
99-04 - 280155784

These have been found to be the best fit for each "generation" of XJ 4.0. Some people sell and recommend the 943 and 700/710' but I wouldn't.

 

Ooops! I meant to type 703 not 710. The 710 fit but still not right.

Good lesson for the OP . . .

 

x2 on the 703's. I tried the 4.0 injectors and had similar issues with rough idle and some backfiring. Kept throwing a code for injector 5.... ditch the 4.0's and get the 703's and your problems will go away.