Hesitating and Popping in manifold area

Hey guys need some help figuring out what is goin on when i start my jeep? Only does it until it gets warmed up completely, it hesitates and you have to feather the gas pedal to get it to go eventually having to basically hammer it to clean it out or something like that. Motor is completely stock with new plugs and wires, distributor just the basic tune up stuff, it also pops like it is having a detination in the manifold at this same time of hesitation. Any and all suggestions would help guys Thanks,

cps or coil is failing once it gets heated up. most likely a bad cps.

mxwild said:

Hey guys need some help figuring out what is goin on when i start my jeep? Only does it until it gets warmed up completely, it hesitates and you have to feather the gas pedal to get it to go eventually having to basically hammer it to clean it out or something like that. Motor is completely stock with new plugs and wires, distributor just the basic tune up stuff, it also pops like it is having a detination in the manifold at this same time of hesitation. Any and all suggestions would help guys Thanks,

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Mine has always had a slight "choke", which is a mild hesitation and small 'pop' under the hood when first accellerating when it's not warm. Only does it once, however. I just gently let off the pedal for an instant and then re-apply.

I got mine at ~28k, it now has 105,6xx. I'm on my third cap/wire/rotor/plugs, 3rd O2 sensor, second TPS (replaced trying to track down what turned out to be a simple bad plug wire), and various other maintenance and tune-up stuff. The little hiccup has always been there and hasn't gotten any worse.... I've read it's fairly common.

Backfiring into the intake is a sign of it being too lean. The only time I have encountered this on an XJ is when my fuel pump was going bad. I would suggest checking the pressure at the rail and see if it is adequate.

Well the check engine light finally came on sorry i forgot to post motor and all 98 xj with the 4.0 auto, had it scanned and it came out that the #1 cylinder is way lean. Was told one of the O2 sensors could be bad they were not sure which one. Funny how the #1 cylinder could be lean when its actually the first injector that is connected to the main feed, not sure it would matter tho as it is pressurized. Idles rough most of the time with an up and down idle. Fuel pump? Bad injector? Coil or wires? When driving down the highway tho it purs like a kitten, any suggestions on where to start. Thanks for the feedback guys much appreciated.