In cylinders 1,2, and 3. Is that likely a spark plug issue? My brother owned it for about 4 years and I have now had it for about 3 years. I have never changed the spark plugs and as far as he can remember he never did either.

Any help would be greatly appreciated.

 

Uhh... Do an ignition tune-up, dude, holy crow...

 

does it run rough after the motor has warmed up?

 

crank sensor....after driving for a while, shut it off, and then start it again...does it idle rough and have trouble keeping rpms

 

Wow, 7 years without a tune up?? Sheesh. Get on that.

 

Most likely your problem is the dreaded #3 missfire (it will cause the two cylinders before it to show misfires) You can get a heat sheild for #3 fuel inj. at the dealer for around 5 bucks it was in a factory breifing for mechanics years ago,also get yourself some heat sheilding for plug wires to wrap all your injectors.Next do a complete TUNE- UP plugs ,plug boots and new springs ( the rubber boots on the bottom of coil pack) also have your coil packs checked. (As far as a cks no its not that.) check the air filter too.This should fix you up for another 7 yrs. My 2000 xj went 5yrs before I had to do a tune up then I wrecked that one.Good luck

 

Change the spark plugs for sure.

If it is that dreaded cylinder #3 misfire, space the back of the hood with about 10 washers per bolt. Allows some better airflow, fixed it for me.

 

Wrap that #3 injector with the heat guard mentioned above.

 

I do ignition tune up every 14 months roughly. That's when I notice it running a little rougher usually

 

Gotta start with fresh plugs. NGK V-Power copper plugs gapped to .035 are a good choice for the 00-01 4.0 engine with the distributorless ignition.

See where you're at after that. Simple stuff first. Always.

 

What do you guys recommend for my older Jeep? I've always used Autolites, they're great and $2 a piece.

 

Champions plugs for all years

 

How much are they? What about the other components?