I'm driving into work today, and just got on the highway. I get a couple of miles down I-95 and notice that it's still friggin cold in the car! I crank the heat to 90 and notice that there's no hot air coming out of the vents. So I'm thinking must be the heater core is clogged or dead, whatever.
Then I notice my engine temp, 220, 230, 240, 250! I pull off and into a Shelll station and just as I'm about to shut the car off, the DIC says "Stop Engine" "Engine Overheated". So I get out and pop the hood, and there's some good smoke coming off the exhaust manifold, so I know the old 4.9 is hot!
I felt the radiator, and it was cold, then I felt the upper radiator hose and that was cold all the way to the thermostat. So now I'm thinking I must have a stuck thermostat. So I call AAA and they come to tow my Cad home. The guy notices coolant on the ground, so I pop the hood again, and look around a bit more and notice that the lower radiator hose popped off of the radiator! How the heck did that happen! I changed the radiator about two month ago, so the only thing I'm thinking is it wasn't tight enough! But why did it take two months for it to just pop off?
Oh well, I got a rental truck, and now have to put the hose back on and make sure it's good and tight this time! I just hope the engine wasn't damaged! I do plan on changing the engine oil since I don't know how hot that got, and it was down to 30% or so anyways. :(

still change that Tstat! lower hose could have popped off if its an old hose.. they weaken. also, the pressure that it reached is not normal temps.... normally it starts cooling way before then :) id check the radiator and hoses for leaks and all that fun stuff, change the tstat and flush the coolant system (not with flush stuff though... just water and antifreeze) be sure to use the sealent tablets the usual.. ive had a similar prob with my 4.5 but that was because of the mistake of using a cheap hose instead of molded for my needs....

I did change the thermostat. I've noticed it runs a bit cooler now. Around 194-207 on the highway. Before it would be 204-212 or so.
Also, the lower rad hose was new! That's what's wierd is how it pops off a month later! This time I made sure it was on good and tight and installed a new hose clamp.
I changed the motor oil, it didn't seem too bad, but at least it's fresh now! So hopefully my problems are over! For now anyways! With 126,000 miles, more are sure to come!

glad to know that its ok , how much did everything run you for ? also how do you read the temperature of the car on the digital gauge ?

its easy to go through the computer on that caddy, its only a few options into the system... hopefully you put some kind of sealent into the engine....

caddy daddy

Congradulations on being wise enough to PULL OVER - STOP ENGINE -
many people try to drive to next exit , etc. ruins the engine or engine is never the same.

You may be aware that there is a wire spring inside the lower hose. This acts just like a stent in a heart artery, keeps it open. The carbon steel spring is a strong clue as to the violent action that can occur. For instance in an old hose the steel spring hinge may rust /break, then a pin hole can develop in hose and the opening of STAT and action of water pump will collapse hose , depriving engine of coolant , sudden dangerous overheat and when you stop engine you will not find a clue! This is RARE occurence but it happens.

This is a little bit of a rant since we all recognize that if vendor would put stainless steel spring inside hose it would never rust. Mfg cost factor.

The water pump may have sucked your semi tight clamped hose off the radiator.

I drive a 94 deville digital DIC and could you explain to me how I can view the TEMP as I drive. I don't kow how to acces that info and I need it badly.

regards

Yeah, if it wasn't for the temp guage setting I have on my car, I wouldn't have known what was happening! I wouldn't have known my engine temp was going up that high without it, and I wouldn't have known I needed to get off the highway ASAP! When I drive my car, I now always have the coolant temp displayed, for just the reason that happened to me last week!
That could be a possibility about the waterpump sucking the hose off the radiator. It is a new lower hose, a little over a month old. That may be it, or it could be it just wasn't tight enough, and the rubber has compressed enough to be a little loose now??? Oh well, at least my car is ok, and I made damn sure that hose clamp is tight now!
Here's the link to the thread here on how to change the DIC outputs:

http://www.cadillacforums.com/forums/showthread.php?t=42347&highlight=deville+dic+upgrade