Hi Guys,

I have a 2000 l6 XJ and recently it has been "Bucking" after I drive it for about 60 miles and if I try to accelerate past 55mph the engine seems to loose power and begin to stall. I changed the spark plugs and the coil pack but the same problem keeps happening. Also about a year ago I changed the crank sensor which fixed a similar "Bucking" problem but I do not believe it is that. Please help me I need this jeep to work properly before I take it back to college in a few days!

 

Maybe get it checked for tripped codes. Even if the CEL isn't on.

 

The Light is on it comes up with a Cylinder 1 misfire. I checked it all out and it seemed to work fine no rough idle, hiccups or anything of the sort. So a turned it off and I like I said before after the engine runs for about 60 miles it runs rough. After I was driving for about an hour this morning a got stopped at a red light and it all of a sudden had a rough idle and the CEL was continuously flashing. The same thing happened to me on Monday but after I worked an 8 hour shift it started up and ran all the way home normally. I had a mechanic at work run a test on it yesterday and he said it was the coil pack according to his high-end scanner so I changed that and the spark plugs, but still the same thing is happening today.

 

if your check engine light is flashing that is for a miss fire. If you alread changed the coil pack and plugs, I would check to see if there is a fuel injector that is not working at the time of power loss.

 

I'll check that out and see if it works.