1998 cherokee 4.0 missing at idel no stall

Hi new here.I have a 1998 jepp cherokee sport 4.0 130.000 miles.Got it last spring.When I first start it and let it idle after about a minute or two it will start missing if I rev the engine it will go away and it runs great.If it sets for 30 to 45 minutes it will do it again.I noticed a hairline chack in the exhaust down pipe by the weld and put some muffler sealer today.Have not drove it sense. could this be the problem? Thanks

Interesting. Could be one of several sensors. You may want to take it to an auto parts store that can put the scan tool on it.

Interesting. Could be one of several sensors. You may want to take it to an auto parts store that can put the scan tool on it.Hi I had a code reader hooked up and it didn't pull any codes.the muffler mender won't hold the heat keeps cracking.I giong to have it welded hope this wll helpThank you for your reply. John

Hmm sensors are fine and it only does it when it is cold. I would make sure you've had a tune up...new plugs could help, as could making sure your air filter has been replaced in the last 15k or so. If you have cap and rotor on your model (I know 99 started with an electronic, not sure about 98) then replace those as well.