Keaton

Hey guys. So the past couple days i have been having overheating problems. It started Friday on my home from work. The temp usually hovers right at 210 but it started headin to the next mark up, ~220. Then it jumped all the way to max, almost, and the Check Gauges light came on. After a couple minutes it dropped back down to the ~220 mark and the light went off. It was fine the rest of the way home and this morning on my way to work, which it hovered between 210 and 220.

Today on the way home the CG light came on and went off a total of 3 times. All with the same symptoms. Cruising on the freeway at 65mph the temp will just start rising to about ~220 and then out of nowhere jump to 260 and the CG light will pop on. It only stays on for about a minute then shuts off. The jeep itself runs good, no smoking/steaming or anything. I thought i noticed a pattern of, if i started to go 70+ it would rise but it might have been just random.

On the off ramp my oil pressure dropped to 0 and the light came on again. Not sure what was up with that.

Ive been reading up on it and want to believe its just the gauge but i noticed my heater is cold when the temp starts to rise. What does this sound like to you guys? I popped the hood once i got home today and noticed a thing on the front of my AC compressor intermittently spinning, even though the AC was off. Not sure what was up with that. Vid/pic below. I replaced the water pump a couple months ago, its ran good at 210 since and I flushed the system but maybe i need to flush it again.



http://smg.photobucket.com/albums/v7...702_190208.mp4

Radi

Did you burp the cooling system after refilling it? Air pockets will do that, as well as cause overheating and erratic gauge operation.

I could tell what era jeep you had as soon as I read the temp needle jumped instead of gradually rising. Yours is buffered by the PCM and once it crosses a certain threshold the needle is driven far right and the light comes on.
You are probably not really operating at 260 deg, Chrysler did this so the "average" driver could easily see which gauge reading was out of bounds.
Oil pressure is buffered as well, FWIW. The fact that BOTH are acting up makes me wonder about connectors, grounds, cluster connections, etc.

Anyway...I don't trust that setup to always tell the truth. Grab an infrared thermometer. Next time it jumps up, check the temp at your thermostat housing. From there you can determine whether you have a cooling problem or a metering problem.

Keaton

I burped the system when I did the water pump yeah.

This morning on my drive to work it did the same thing. After I got off the freeway the jeep just died. The temp was at max, the oil pressure dropped and the CG light was on. Took almost a minute of cranking to get it started again and it was smokin the whole time I was trying to start it. When I finally got to a place to shut it off I popped the hood and there was smoke coming from the engine. It runs like crap and will barely idle without my foot on the accelerator. Not sure what to do since im now at work.

Muaddib420

Blown head gasket or cracked head.

Parsnip

X2
Cold heater plus temps that high...also have you checked coolant color/oil color/levels

Keaton

Figured as much.

I have lunch soon so ill go out and check the oil and coolant. Anything I can do to limp this thing around til the weekend?

Parsnip

Not drive it...i mean you could but then it becomes a 2 grand motor not a 100 dollar gasket set...sorry :/

Keaton

Ok so I just went out and checked it out. Oil is not milky at all, its about a quart low but its dark. Exhaust doesn't smell sweet. The coolant is a little too dirty for my liking but I think that might be due to the radiator being dirty. I burped the cooling system. I let it idle for about 10 minutes and it ran fine. It got up to 210 and stayed there. The heater blew hot and even with the AC on it didn't get any hotter. Not sure what this means.

Keaton

Another update. I've let it idle for about 10 minutes a couple separate times. It hasn't gone past 210. I took it for a little drive around the block and it seemed ok.

Though it does hesitate when I'm taking off from a stop. And when I'm in Reverse the idle gets all funky and drops down to about 250 and sounds real rough. Any help?

I'm thinking I need tobreplace the thermostat first. It seems to me that its heating up after awhile because the thermo never opens. Not 100% sure on that though.

wmmccall

For sure.

wmmccall

You can't be saying the RPM's drop down to 250? Even if it's 2500 RPMs in reverse that seems high.

Radi

While you're at the FLAPS buying a thermostat, borrow a cooling system pressure tester. Most have a loan/rent program for that stuff.
Pump it up to the cap pressure rating and see if it leaks down or holds.

Parsnip

It doesnt idle or run rough when on highway? Lifter clicking or anything? I mean its a little hard to tell atm but now.im thinking maybe bad thermo like you said....idk im a noob at diagnosis

Kalali

Given the OP's update, I think a defective head gasket diagnosis is somewhat prematured at this time. That said, given the 00-01 defective head reputation, if the engine did indeed overheat, the head is most likely cracked now. Speaking as one of the victims of the 0331 cracked head, if it were my rig, I would really pay close attention to the coolant and oil levels - coolant level going down and oil level going up, and replace the head immediately if I notice any change. Unfortunately just replacing the gasket will not help.

Parsnip

Isnt there a way he can swap the 0331 with the newer one?