Hi all, firstly apologies as I've posted about this issue a couple times and in different places but im still having issues and in need of some advice, and am hoping that by posting again it might gain a few new eyes and some new interest.
I recently picked up an 04 TJ 4L with the 42rle auto transmission. Upon driving it home about 6 hours from where purchased I noticed an issue where it lost power in what I could only describe as waves, it lost it then immediately came back and then lost it before coming back again and then was completely fine for about an hour before happening again. This doesn't happen as often however still does both on and off the motorway.
The other issue is that when it comes up to temperature (ive never experienced it when cold, it generally starts to present itself as soon as it gets up to temp) it has an extremely rough intermittent idle that often results in a stall if not shifted into neutral and reved to keep it going. I originally thought this was to do with driving at highway speeds as it lost almost all power after coming off the motorway when I first got it but gradually ive started experiencing the stalling rough idle more and more and most importantly not just after coming from high speeds.
Some times it won't happen at all, other times it happens every traffic light. Most of the time once its moving again its good to go when others it has a lack of power when moving off. The strange part is it can go at one set of lights and then clear driving say 50meters and then be fine at the next stop.
The steps ive taken so far, Ive checked for codes and had it read externally, 0 faults. Ive cleaned the IAC and tb completely, no change. I thought it could be fuel pump related but I thought the fact it would rev up on command and start first time every time made me stray away from this. I also considered a sticky/faulty lock up torque converter but the issue happens when the overdrive hasn't engaged and has only been driven at slow speeds, so I wasn't sure if this ruled that out as well. Vac lines would cause an increase in revs not a reduction so that rules that out. I know for a fact it had O2 sensors replaced a month before I bought it so could this be causing the issue? is there a surefire way to test these rather than just replacing all 4 in the hope it helps? Im trying to contact the garage that done the work and see what brand were installed. I had also considered a fault in the PCM but considering the seller stated it ran 100% before I got it I believe it could have been something wear related from the journey home rather than a more serious problem.
The reason for posting again if ive just been out a drive and had the usual wanting to stall at lights but I also had a complete lack of power, the jeep was moving but pushing the gas to the floor resulted in nothing. On top of this at idle it sounded like an old tractor engine spluttering. When retarted it started right up drove perfect for about a minute and then lost power again.
Im unsure but would presume all three of these issues are all connected to one thing?
what else would you all suggest to try? im at a loss at this stage, any help would be vastly appreciated, and apologies for both the long post and at the repeat post, its just difficult to diagnose and what makes it worse is im in the uk so there's a distinct lack of jeep specialists with the nearest being 3 hours drive.
thanks
zach
I recently picked up an 04 TJ 4L with the 42rle auto transmission. Upon driving it home about 6 hours from where purchased I noticed an issue where it lost power in what I could only describe as waves, it lost it then immediately came back and then lost it before coming back again and then was completely fine for about an hour before happening again. This doesn't happen as often however still does both on and off the motorway.
The other issue is that when it comes up to temperature (ive never experienced it when cold, it generally starts to present itself as soon as it gets up to temp) it has an extremely rough intermittent idle that often results in a stall if not shifted into neutral and reved to keep it going. I originally thought this was to do with driving at highway speeds as it lost almost all power after coming off the motorway when I first got it but gradually ive started experiencing the stalling rough idle more and more and most importantly not just after coming from high speeds.
Some times it won't happen at all, other times it happens every traffic light. Most of the time once its moving again its good to go when others it has a lack of power when moving off. The strange part is it can go at one set of lights and then clear driving say 50meters and then be fine at the next stop.
The steps ive taken so far, Ive checked for codes and had it read externally, 0 faults. Ive cleaned the IAC and tb completely, no change. I thought it could be fuel pump related but I thought the fact it would rev up on command and start first time every time made me stray away from this. I also considered a sticky/faulty lock up torque converter but the issue happens when the overdrive hasn't engaged and has only been driven at slow speeds, so I wasn't sure if this ruled that out as well. Vac lines would cause an increase in revs not a reduction so that rules that out. I know for a fact it had O2 sensors replaced a month before I bought it so could this be causing the issue? is there a surefire way to test these rather than just replacing all 4 in the hope it helps? Im trying to contact the garage that done the work and see what brand were installed. I had also considered a fault in the PCM but considering the seller stated it ran 100% before I got it I believe it could have been something wear related from the journey home rather than a more serious problem.
The reason for posting again if ive just been out a drive and had the usual wanting to stall at lights but I also had a complete lack of power, the jeep was moving but pushing the gas to the floor resulted in nothing. On top of this at idle it sounded like an old tractor engine spluttering. When retarted it started right up drove perfect for about a minute and then lost power again.
Im unsure but would presume all three of these issues are all connected to one thing?
what else would you all suggest to try? im at a loss at this stage, any help would be vastly appreciated, and apologies for both the long post and at the repeat post, its just difficult to diagnose and what makes it worse is im in the uk so there's a distinct lack of jeep specialists with the nearest being 3 hours drive.
thanks
zach
