OldLaredo

Sorry in advance I can't give any details on past repairs at all, but have some questions about my friend's 96 XJ.

He just got back into town (barely) and I'm letting him leave his Jeep at my place so we can figure out what's wrong with it. I do know it just had the power steering pump replaced.

As far as symptoms it has a loud hard stutter that seems like it's missing on a cylinder, and seems like it wants to die, but there's definitely exhaust coming out of engine area, so I'm wondering if maybe a cracked manifold could make it run rough like that.

He mentioned something about a mechanic replacing a fouled plug (just one??) but I don't know what's up with that.

Also, he's apparently been running without a cap on the coolant reservoir. It was way over filled (to the top!!), and looked sludgy and gross. I stuck a finger in and it came out nasty and slimey dirty. I initially thought head gasket or something, but there's no water in the oil, and when I started suctioning off some of the coolant I realized the sludge was just at the top. The coolant underneath is ugly (brownish green), but very much watery. Inside the radiator fill hole there was a bit of a sandy (but not gritty) deposit, but the fluid was liquid, not sludge or foam.

His front PCV valve is busted so there's just a hole with the tube next to it, and his firewall on the hood is all sorts of oily.

That's what I've got so far (aside from a leaky fuel tank ). Do you think oil/dirt/water/whatever could have just been collecting on top of the fluid in the res and created that layer on top? Would oily water from a headgasket separate eventually like that?

I have some extra plugs so I'm gonna throw those in for him. And I'm gonna convince him to get another gas tank so we can get that crap handled and done with. But should I be worried about head gasket or cracked head right now? Or just maybe do a tune up, change fluids, and put a new exhaust manifold on? (Have muffler shop do manifold maybe??)

I've got the Jeep here so can answer questions about stuff or take pics if needed.

Bocefus

Yes, check for a cracked manifold. Also check for a vaccum leak that might cause the rough running. The PCV valve needs to be fixed. Thats likely part of the rough running issue as well. The coolant might just be dirty from the busted PCV contaminating it with oil. If it reaches the hood, it can also reach the coolant if the cap is missing as stated. I wouldn't worry about cracked head or headgasket unless its overheating, water in the oil, or blowing white smoke out of the exhaust. Plugs are really easy to change, so thats a given. Sounds like your friend needs to maintain his Jeep a little better. If you or your friend can't figure it out, a good shop should be able to diagnose it quickly for a fair price.

OldLaredo

Yeah I'm definitely gonna have a little chat with him about proper maintenance. When I opened that hood and saw the missing cap on the res (and he said he's never had one), and the busted PCV I almost threw up a little in my mouth.