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Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go hereXJ (84-01)
All OEM related XJ specific tech. Examples, no start, general maintenance or anything that's stock.
My 99 jeep XJ 4.0L has 151,xxx on it. It's well maintained. regular oil changes. And yet is still mysteriously loosing antifreeze. New radiator. New hoses. No smoke from the tail pipe. Runs great. No oil pressure loss. Never overheats. Oil looks and smells normal . And yet, I still have to add coolant every month. Where is it going!!!!!!!!!! dammit
My 99 jeep XJ 4.0L has 151,xxx on it. It's well maintained. regular oil changes. And yet is still mysteriously loosing antifreeze. New radiator. New hoses. No smoke from the tail pipe. Runs great. No oil pressure loss. Never overheats. Oil looks and smells normal . And yet, I still have to add coolant every month. Where is it going!!!!!!!!!! dammit
Go to Autozone (or another local parts retailer) and pick up the cooling system pressure tester tool. It'll be free (with a deposit while you have it) - put it on the system and put some pressure on there and it should be pretty obvious where the coolant is leaking out. Look for the cartoon-like spraying of coolant.
Go to Autozone (or another local parts retailer) and pick up the cooling system pressure tester tool. It'll be free (with a deposit while you have it) - put it on the system and put some pressure on there and it should be pretty obvious where the coolant is leaking out. Look for the cartoon-like spraying of coolant.
X2 on this. If you have no visible loss of coolant, its going somewhere. If you usually park in the same spot, see if there are any drips. Also, about how much coolant are you losing. You may have a small leak when hot, that is getting burned off before it drips anywhere. Theoretically, the pressure test will help you find this. Let us know the results.
You could be leaking in the heater core as well. You can view the tops of the pistons thru the holes for the spark plugs with a boroscope. If you have a hole in a hose, then it might be very difficult to find weeping without putting the system under pressure as stated above this post.
A 99 should have a distributor. Coil rail started in 2000 for both XJ's and TJ's.
Right but the reports of some late 99's having 0331 heads said they had (needed) coil rails. Wondering if any of that was (is) true or just net fodder.
Hmmmm, certainly plausible but I've never seen anyone mention it.
I've seen a lot of people mention "late 1999 XJ" but I never seen any evidence either. If they do exist, they would most certainly have a coil rail if they were from the factory.
The myth (if it is indeed a myth) may come from the wiki reference about the intake change.
In the middle of the 1999 model year, vehicles with the 4.0 liter engine received a much improved intake manifold.
A 99 should have a distributor. Coil rail started in 2000 for both XJ's and TJ's.
The 99 WJ had the coil rail system. The XJ and TJ got it in 2000. My WJ was built in August of 99, sold as a 2000 model. They all have the 0331 redesigned head that made the exhaust passages too thin. The coil rail was installed using the waste spark program where 2 spark plugs fire at the same time every revolution; one on compression and one on exhaust. This was to clean up emissions. The XJ and TJ still kept the old block, but had the 0331 head.
There is more to the 99-07 "clean block" 4.0. The motor mounts were relocated so the 4.0 would fit on the 4.7 mounting locations in the WJ. In doing this, the oil filter and distributor had to be moved as well. The distributor became the cam sensor because it was small enough to fit, but the oil filter was moved to the side of the block near the lifter oil gallery. I probably should have said the motor mounts were moved rearward in the WJ to balance the 4.7 V8 because of the space required for the timing chain case. This required the 4.0 block to be modified to make it fit in the same vehicle. Contrary to popular belief, the 4.0 was produced until 07 for replacement units. I also was told it was still used in the TJ until they became the JK. The main reason the 4.0 was eliminated as a standard engine was because they couldn't make it meet increasing high emission standards, plus the fact that it was heavy and too long and tall to fit newer body styles. It seems that short stroke, high reving engines are cleaner on emissions.
For those of you planning on replacing the 0331 head, there are aftermarket heads available, notably the "Clearwater head cast with more metal, and the 02 "TUPY" head. This is still an 0331 head, but recast by the Tupy Foundry in Brazil using more nickel in the pour resulting in less tendency crack. You can see the letters "TUPY" cast into the head by looking down the oil filler hole with a flashlight.
04-03-2019, 12:45 PM
99 XJ coolant leak
