-Dom-

Okay here's what's going on
Everyonce and a while I will start my xj and it will have a really rough idle and sounds like its gonna stall, when you give it gas its not very responsive and still seems like its gonna stall.
I changed my oil today and it was like what in the oil filter.
I've changed the spark plugs also
No leaking visable around head though
Good friend says its the head gasket is this true?
Also if u can let me know how much it is gonna cost I would like that.
Thanks for your time
Dominic

-Dom-

Btw its a 01 cherokee 4.0 str8 6

tjwalker

Truthfully, there are a lot of things that can cause your symptoms.

Start with fresh plugs, gapped to .035 The NGK is a very good plug for the 00-01 XJ with the distributorless ignition.

The 00-01 has the "infamous" 0331 head. Has this engine ever been overheated? That can lead to a head gasket or a cracked head, especially because the 0331 head is more prone to cracking because of the casting defect between cylinders 3-4.

Are you using any coolant from the reservoir? The #1 symptom of a cracked 0331 head is "unexplained loss of coolant".

UserID6095

To check the head gasket you need to perform a compression and leak down test. Check the oil for coolant. Check the coolant for oil.

Do you have a Check Engine Light (CEL)?

-Dom-

Okay how do I do that just look at the coolent?
And yes the light is on

1991Jeep_Man

Follow these steps in order:

Go to Autozone and have them scan for your CEL. That will give you a code for what's causing your issue.

Next, pull your oil dipstick and check for anything milky white on the end. If not, then just put the dipstick back in.

Check your coolant overflow (clearly marked via a title that says "COOLANT ONLY"), open it and check inside to see if you're low.

Next, pop your oil cap and look down inside with a flash light to see if any crack is visible.

Perform a leak down test (while your at autozone, inquire about this)

Perform a compression test ( also inquire while at autozone... they usually have the tool to do this. Not hard at all)

Doing these steps should provide you with a definite answer to your problems.

UserID6095

Well the CEL is good and bad; Good, go to your local Auto Parts store and have them pull the code for you. Write it down and post back with it. That will help us get you started. Bad, total engine failure but lets hope for the best.

Is the coolant brown? Pull some out of the rad and put it in a container. Let it sit for a while to see if any oil separates from the coolant. You can do the same with the engine oil. A milky or shinny surface would indicate oil/coolant mixing.

While at the parts store see if they can rent you a compression check 'kit.' Post up the numbers once that is done. A leak down test would help but not as important as a compression check.

You have now be assigned some homework, good luck.

Edit: A minute too slow...

1991Jeep_Man

http://www.automotiveforums.com/t212...r_misfire.html

Also, look at this and compare the results of your code test to it.

Gee oh Dee

I'd do an oil change. Although this isn't a definate answer, if you've got any milky white/grey/brown sludge in your oil you've probably got a bad HG. If not, you probably don't.

Are you missing any coolant? If not, its probably not a head gasket.

You can bridge a coolant jacket or oil jacket with the combustion chamber and not with each other, so you may not see oil in the coolant or the other way around.

Really the only easy way to tell is looking for loss of coolant or oil.

But those aren't for sure ways either.

cherokeeaddiction23

i just had the same thing happen to my jeep, its in the shop now getting the head gasket replaced, i would do it myself but i dont have any time to do it, i had bad compression in cylinders 2 and 3, and im not loosing coolant and the oil is fine, so its gone between the two cylinders which isn pretty common, that explains why i couldnt figure out what was going on

zraffz

Are you running coolant or water?
symptons of a bad head gasket:
- Oil is a "milky brown or white" and usually higher than the recommended level
- Plugs have coolant on them
- Smoking excessively out the exhaust pipe

Or you can go buy a $15 Compression gauge from the local automotive store, pull a spark plug and screw it in. Have someone else crank and read the pressure it reaches (should get to at least 120ish PSI). Repeat for each cylinder. If they all yield around the same low result you know the problem.

As stated, the center section of the head gasket could be blown between two cylinders and that won't allow the coolant to mix with the oil.

-Dom-

Wow that's for all your input!!!
I check the oil last night it was milky and driping off the dip stick, so I canged it
The oil in the filter was like water driping off and very thin
I was low on coolant and filled with water (in florida so its not gonna freeze)
I'm going to do my home work tonight or tomorrow, ill keep u guys updated

Gee oh Dee

Loss of coolant + milky oil = no bueno.

Sounds like a HG.

XtreamJ

Compression test ???? And if your decent with a wrench you can fix a head gasket in the 4.0 for about 50 bucks H gaskets around twenty bucks and new head bolts are around thirty so seeing that the valve cover gasket is reusable just leave the manifolds bolted to the head and lift it straight off. Last one I did took me around 3 hours it's a very simple top end

tjwalker

Usually, with those symptoms, it is a cracked 0331 HEAD, rather than the head gasket.

The 0331 head has a known casting defect between cylinders 3-4. Known to crack.

And losing coolant from the coolant reservoir without an external leak is a big clue to this.

This head is a dog. Be aware of it..........