My nephew just got his first vehicle, a 2001 4.0 Cherokee Sport with 150,000 on the speedo. Right off the bat he had to have a radiator and now it is running rough especially on cold mornings. The check engine light came on and reading them indicates a P1494 and a P0300.

Read up on the valve/carbon problem that there was a TSB out on. However, the vehicle does not exhibit rough running or missing when under a load or while cruising on the Interstate at higher revs so I am thinking perhaps this isn't the problem.

It idles very rough on a cold start and even when warm it does not idle as smooth as it should, it still feels a bit rough. Being a kid he doesn't have a pocket full of money to start throwing at it. I thought this might be a good place to start looking for pointers.

Thanks for your help up front.

 

Try this website, it has helped me out too many times....

http://www.geocities.com/dtmcbride/h..._dtc_jeep.html

 

P0300 means there's a misfire in one or more cylinders. I had that problem with my '96, it cleared up a little bit when I replaced the cap, rotor, plugs and wireset but it still runs a little rough on colder mornings. Mine also runs rough after I push it pretty hard (pedal to the floor for a sustained period of time), does yours do the same thing?

 

I had a 2001, with the same issue, mine ended up being the coil pack for one of the cylinder, the bad part is, it's all one piece have to replace all 6