Check Engine Light

Has anyone had these problems? I bought a 2000 Jeep Cherokee Sport with the 4.0 I6 on 11/10/04
Check engine light has been on 12 times cylinder #3 misfire
Check engine light was on 4 times O2 sensors
1) check engine light comes on after idling for 30-60 minutes and sometimes just comes on during normal driving
2) idles rough especially when cold
3) sometimes dies after start up
4) sometimes hard to start

11/12/2004
Replaced air filter
Cleaned battery terminals

11/28/2004
Checked gas cap

11/29/2004
Replaced spark plugs

12/10/2004
Ran complete fuel system cleaner and octane booster through tank of gas

12/30/2004
Replaced coil pack
Checked injectors replaced #3 injector and inspected injector wires

12/31/2004
Ran fuel stabilizer through tank of gas
Installed heat barrier tape on injectors, fuel rail and intake
Turned #3 injector to 2 o'clock position

1/03/2005
Replaced spark plugs

1/03/2005
Installed heat shield between intake an exhaust manifolds

1/04/2005
Dealer ran system diagnosis, unable to find any problems

1/05/2005
Dealer checked to make sure debris shield had been installed and checked codes, found no problem

1/19/2005
Dealer checked and found bad engine


1/20/2005-1/24/2005
Replaced engine (refurbished engine)
Exhaust Repair

1/28/05
Dealer found O2 sensor bad

2/01/05
Dealer replaced both O2 sensors

2/04/05
Dealer found O2 sensors bad again

2/04/05
Dealer relaced both O2 sensors again
Removed and cleaned out muffler

There is a tsb on #3 injector becoming to hot and not working on hot start-up. The dealer put a insulation sleeve on number three injector and reprogramed the computer. I still think it misses on hot start but no code

Sheeeesh, MountainWarrior! You should ask Wascobi if you can borrow his thread title:
" ready to burn this mother@#%&"

Today they cleaned the catilatic converter and replaced the thermostat.

have had the same problems...
i am currently going though options, but dont have money to fix.
#3 cyl seems to be a problem...
my first fix was a new battery, but after four months its starting to do it again...
so new battery? or dig deeper item by item...?
honestly, i think some of the 2000 sports are factory lemons...as if somebody on the assembly line that day was 3 sheets. i have two friends same vehicle similar problems...
i hope things start to look up for you soon.
N

There is a website out there, I can't remember the URL, that allows you to put in problems that you have with your vehicle. The purpose is to force the manufacturer's to do recalls. It sounds like we need to get proactive and start holding the manufacturer's feet to the fire.

I have long thought that the CPS problems need to be a factory recall.

Talk about throwing the baby out with the bath water. Your dealer forgot to give you the software upgrade to the engine CPU along with the sleeve on the injector. I had the same problem with my 2001 at about 27,000 miles - wouldn't stop misfiring. Got the MIL and the #3 cylidner misfire about once a week. The dealer would reset the CPU and all would be fine for a week or so.

I went to a different dealer and they told me there was a software upgrade that needed to be done along with the sleeve on the injector.

Not a problem since then.

i have a 2000 with the same problems sometimes i get a 1 and 3 missfire with a multiple missfire thrown in for good measure. ive done everything youve done except for the bad engine thats just amusing. ive even swapped my sisters computer into my truck still same f ing problem. did u get that upgrade or is that bs too/????

there is also a bulletin about replaceing the valve springs for this problem
has worked on a couple 4.0 jeeps have done at my dealership.
1st bulletin was to turn the valve springs
but might as well replace them if you are going to do all that work.