Topic: Sudden rough idle and hesitation

[JeepGeek666]

My '04  2.4L  wrangler has a little over 103K on the odo and I have taken fairly good care of it and the engine since Ive had it.   All of a sudden today, the engine starts idling funny.   I deliver pizzas and my jeep is my only vehicle and during a delivery, out of nowhere, i get back in the jeep and its shaking a bit like the engine is struggling to stay on.   I give it a little gas and it stops doing that.    For the rest of the day, I had not one problem.     Then, after work I go to the carwash to get 40 tons of road salt off (even washed under the hood a bit with degreaser) and fire it up after im all done..... rough idle.      The RPMs did not move up or down, it just felt like a hesitation.    Then while accelerating in 2nd 3rd and 4th, the engine hesitates and bucks a bit until i hit higher RPMs
 
Figures..... maybe its water?   Im hoping nothing serious.  I did a code check and nothing popped up, odometer said DONE...   

[chardrc]

after the car wash it could have been caused by water on / in the distributor / spark plug wires.. or some electrical connection... salt sucks... hard to keep vehicles clean.. on a side note the grease / oil will prevent rust so keeping that on until spring may pay of( or thats what I tell myself since I don't feel like degrease mine) ....

[JeepGeek666]

hmmm.... perhaps in the spark plugs then??   Never considered that.    mine doesnt have a distributor in the old sense... its  a coil pack i belive.....  all electronic.   The thing I dont get is, I felt this rough idle earlier in the day before I got the engine wet but I had no hesitation.

[rcopes]

Always start with the basic, Dry the cap and rotor, run some seafoam through the gas tank, and raise your hood in the dark and look for a lightning show.    lol

[chardrc]

ops didn't pay attention to it being a 2.4l....

[Treeslam]

My 94 2.5 was rough idle so over a weekend I changed the fuel filter, plugs, rotor, cap, O2 sensor, put a bottle of seafoam in as I filled up the tank. While no miraculous power change, there was an obvious change in the engine smoothness.  I especially notice when I let off the throttle.  Where it used to cough and sputter, now just purrs like a well tuned kitten.

[JeepGeek666]

swapped out my plugs.  I had champins, put in some BOSCH platinum 2 and things seemed to be fine from there.   I'm not quite ready to start messing with the harder stuf yet but the plug swap worked so far.    I'd like to put a performance ignition in.  I saw the screamin demon coil packs and they look interesting.   That, a set of 8mm wires and the upgraded plugs would be nice.   

[jfrabat]

swapped out my plugs.  I had champins, put in some BOSCH platinum 2 and things seemed to be fine from there.

To be honest, I have not felt any difference between the premium sparkplugs and the cheap ones.  In fact, I prefer the cheap ones because you can gap them for hotter ignition systems like what you intend to get (IIRC, the PD can be set up to .060 or so; mine are gapped at .045 or so, though).

I'm not quite ready to start messing with the harder stuf yet but the plug swap worked so far.

I recommend you get a Haynes or Chilton manual (or both) and download the FSM from this site (search for it and you should find it) and bu a good torque wrench.  With that, you can do almost any repair to the Jeep.  It is as simple as following instructions.  Take X part off.  Torque to X ft/lbs.  Most procedures are very simply once you get this...

I'd like to put a performance ignition in.  I saw the screamin demon coil packs and they look interesting.   That, a set of 8mm wires and the upgraded plugs would be nice.

I recommend you get the complete PD package (which includes the Screaming Demon coil) and use their LiveWires.

[Jeffy]

To be honest, I have not felt any difference between the premium sparkplugs and the cheap ones.  In fact, I prefer the cheap ones because you can gap them for hotter ignition systems like what you intend to get (IIRC, the PD can be set up to .060 or so; mine are gapped at .045 or so, though).

.065" actually.  And it did make a difference.  I don't feel it as much as hear it.  It runs a bit smoother at higher RPM's.

[JeepGeek666]

I got a subscription to ALLDATAdiy for my jeep the other day.   Lots of useful information on there but i would like to get an FSM as well.    The BOSCH plugs say they never need to be gapped due to the double electrodes and what not already producing a bigger spark.    I dont know much anyway so maybe they lied to me and need to be punched in the teeth ha ha.   

I can follow instructions fine.......its just the thought of messing something up that scares me.     Build a model?  no problem.     assemble some toy for my kid.....easy.     But the thought of getting deep in the guts of the jeep and going HUH??? freaks me out......lack of confidence.   Maybe once its paid off in a year or  I had another vehicle to drive while fiddling with the jeep....wouldnt bug me so much.   

I lack garage space, only have so much time in a day and my tool kit consists of one socket wrench, a torx bit, needle nose pliars and a paper clip.    If I were MacGuyver I could repair a nuclear sub with them.