2000cherokeexj4

Hi I have a 2000 jeep cherokee sport. When I drive it for a while it runs great but when I turn it off for 5-10 minutes and turn it back on it runs rough like it is kinda chugging along until I rev it up a bit the. It runs fine. What could this be?

PurpleToxin505

i Have the same issue, pretty sure its the plugs or wires. Something with ignition because Im running pretty rich. Im gonna do a full tune up some time this month, Ill let you know if it goes away.
When yours does it, say you start it up in the morning to let it warm up, while idleing it runs a lil run but it kinda revs it self up a lil and corrects it?

benja455

It's a well know issue. There's a TSB about it...just do some searching. It will also cause you to throw a code for a cylinder 3 misfire.

Dumajones

Found this for ya


TSB1803103 - 4.0L ROUGH ENGINE IDLE AFTER RESTART FOLLOWING A HOT SOAK
Date: 09/05/03 (supercedes 1802702 dated 09/06/02)
Model Year(s): 1999-2004

Description: NOTE: This bulletin applies to vehicles equipped with a 4.0L engine. This bulletin involves the installation of a fuel injector insulator sleeve.

Details: Customers may describe a 20 to 30 second rough idle following the restart of a heat soaked engine. This condition may be most noticeable when the engine is restarted following a prior 10 to 20 minute heat soak in hot ambient conditions of approximately 32 C (90ºF) or higher. This condition may be consistent with short city stop-and-go driving trips and can be aggravated by the use of fuel with a high ethanol content. Depending upon various conditions a MIL may occur due to DTC P0303 - Cylinder #3 Misfire.

This condition may be caused by heat from the exhaust manifold that following engine shut down migrates to the area around injector #3 and causes fuel vapor to form within the injector. This in turn may cause a momentary misfire of cylinder #3 until the fuel vapor is cleared of injector #3. The insulator sleeve lowers the injector #3 temperature to a point below which the fuel will not normally vaporize.

If vehicle exhibits a rough idle, and if a misfire of cylinder #3 is observed following a 10 to 20 minute hot soak, perform the Repair Procedure.

Parts required:
56028371AA Ignition Wire Shield

Repair procedure:
1. Cut insulator sleeve, p/n 56028371AA, to make two (2) insulator sleeves about 25-30 mm (1 in.) in length. See diagram.
2. Install one sleeve around injector #3, with the slit on the upward facing side of the injector. Install the other sleeve with the slit on the downward facing side of the injector.
3. Confirm sleeve is flush to intake manifold surface around injector.
4. Check injector #3 wire and ensure that the injector is rotated to a 2 o'clock position. __________________

jbdpayne

x2 def sunds like heat soak which is common for that year (my 01 does it too). Give that a search you'll find a few write ups on it!

2000cherokeexj4

Ok thanks I'll give that a try

2000cherokeexj4

Hi I have a 2000 cherokee xj that's needs a new electric cooling fan and I'm pretty tight on money I found some universal fans but before I buy one I wanted to make sure it would do the job. And how to hook one up cuz they don't have the plug to plug it in it just has red and black wires

Turbo X_J

You can always cut the connectors then solder and heat shrink. If the universal fan fits and moves air the same direction, you are good. Not sure what the auxiliary cooling fan question has to do with the heat soak thread tho...

Heckler1963

Hi guys I need help with something. I have a 2000 XJ 184.00 miles and I'm having the rough idle on restart problem. I installed new manifold heat shield, heat wrapped fuel rail, heat wrapped fuel line and heat wrapped all six injectors, installed new 4 hole injectors,new coil pack and new spark plugs. Installed new MAP sensor, idle air control valve, and throttle position sensor. Checked fuel pressure, gauge was jumping around so i installed new fuel pump now fuel pressure is at 49 psi steady. Did compression check all cylinders were 148-149. Did a leak down test all good. Checked for vacuum leaks none found. Still have problem. I'm the original owner and never had this problem till this year. Anyone have any ideas? Really could use some help. This problem is driving me nuts!

Ralph77

I have read a lot about Heat Soak issues over the years. Thankfully in my '00 I don't experience them. Since you have already addressed the issue with heat shielding, among other things, I have to ask what plugs are you using? I run the cheapo Champion Copper Tops. The old number is RC12ECC which now crosses to 438. Still has the old number on the plugs along with the new one the last time I bought some. Also is this a recent development? Reason I ask is winter blend gas. I have read that some guys have solved this problem by running ethanol free gas. No idea about this, just something I have read, and also understand that ethanol free gas is not an option in many areas. Other things that I have read about are putting vents in the hood to let out the heat. Putting those risers in the back of the hood for the same purpose. Setting up the electrical fan to run for a bit after shutting off the Jeep. Again for the same purpose.

mikesignal

make sure your cooling system is working properly--clutch fan, water pump. electric fan-- and has been serviced (coolant changed). Also transmission fluid service. If your coolant is discolored or your transmission fluid looks dark it is not helping your situation. You should not be having heat soak in winter--check your operating temps with a scanner, do not trust the gauge. and lastly, are you losing any coolant? make sure your overflow bottle is at the full mark, and it stays full.

moparado

AHH, the infamous heat soak issue. Been there, done away with it.
Installing the TSB hardware helped but didn't completely solve the heat soak on extremely hot days with an extremely hot engine then parking for 15 min.

I ended up installing a push button on demand delay circuit that keeps the electric fan on for about 4 minutes after i shut the engine down. Also comes in handy on hot days waiting in line at the drive thru where i can turn the electric fan on before the Jeep does.

Sizemic2

Do you have a parts list or have you considered doing a write up on this?

mikesignal

not exactly a write up but there is a link to cherokeetalk on the first post which has the wiring diagram

https://www.cherokeeforum.com/f67/el...166945/index2/

moparado

What it amounted to was buying a 12volt delay printed circuit board from Amazon, if i remember it was around $6 or $7 i forget but is was inexpensive, a momentary push button switch, a small plastic case, fuse holders, wire, a terminal strip and a 12V relay complete with socket.

I had a small plastic case, terminal strip, wire and fuse holders laying around. The whole cost was under $20 for me. The case and relay are also dirt cheap at Amazon.

That delay board is a little tricky at first to program. But once the jumpers are placed, the onboard potentiometer allows a wide range of delay adjustment with only a small screw driver. Its been working great for well over a year now.

The way i wired up the delay board, there's no current draw once it times out...a potential battery saver.

I also explored an automatic delay when the engine was turned off but that was more complicated and would allow some current draw when it timed out.
I like the manual push button better as i don't need the fan delay in the Winter and i can energize the fan delay any time by pushing the switch.

If there's enough interest, yeah i can do a write up complete with the major P/N's i used but it would take time to look up the P/Ns.