: Overheating problem...



Lebowski
10-14-08, 02:20 PM
My '99 Seville overheated today on the freeway for some reason. I made it home and removed the cap so it could cool off. It was pretty hot. Anyway, can I just put in some antifreeze mixed with water or do I need to use something special? Also, the "service engine soon" light came on so how can I get it to go off? Why would it overheat? I did get up to 90 for about a mile but that shouldn't cause it to overheat, should it? Thanks in advance....

Submariner409
10-14-08, 02:55 PM
There are so many threads and posts on overheating Northstars that it would be impossible to list them all. A bit of homework searching in here and Northstar Performance will answer all your questions. As well as offer tests and diagnosis.

Your engine had DEXCOOL installed as standard. Is your coolant sort of yellowish-orange ? If so that's DEXCOOL, so use a 50/50 mix to fill the surge tank to halfway, cold, and drive a bit, let the engine cool down to barely warm and fill to halfway up the tank, no more.

Lebowski
10-14-08, 03:10 PM
The coolant is all over the driveway so it's hard to tell what color it is. Can I fill the tank with water to see if it overheats? If I fill it with Dexcool and it overheats all over the driveway wouldn't that be a waste of money? Do they sell Dexcool at Walmart or do I have to go to an auto parts store? Thanks for the info....:yup:

Submariner409
10-14-08, 03:16 PM
Did the coolant blow out all over the place when you took the cap off (which was a no-no), or did it leak out of somewhere after you shut the engine down ? This info is critical in the way the coolant wound up on the driveway.

DEXCOOL is available at just about any place that carries car stuff, including WallyWorld and the other big box stores.

Lebowski
10-14-08, 04:11 PM
I didn't see any leaks-just steam coming out from around the cap. Do I put in straight Dexcool or do a 50/50 mixture with water like on a normal car? I'll pick up a couple of gallons with the Stude and fill up the radiator after dinner and take it for a spin....

Submariner409
10-14-08, 05:33 PM
50/50.......Post #2.

Steam coming from the cap is not a good sign. Check your Money Market.

Ranger
10-14-08, 06:27 PM
Check the tank to be sure it is not cracked and then make sure that the cap is still holding pressure. Also make sure that the water pump belt and tensioner are intact and in good working order for starters.

Lebowski
10-14-08, 07:08 PM
I put in about a gallon and a half of Dexcool and water and drove it 3 miles after letting it idle for about 15 minutes. The gauge went straight up to the H for Hot so I headed for home. When I slowed down to about 30 (from 60) the temp. gauge started going down to about 3/4 but it was still flashing "shut off engine" and "change oil" also. When I parked it and opened the hood there was no steam coming from the cap and there was nothing leaking from anywhere under the front of the car. It's almost dark now so I guess I'm done for today so what should I check for tomorrow? How do I do that search for a code number? Any other suggestions? Thanks for the help so far....:)

Ranger
10-14-08, 07:30 PM
If the things I mentioned in post #7 are all OK and the purge line is clear and flows coolant, have the coolant tested for the presence of exhaust gases.

tateos
10-14-08, 09:49 PM
HG...sorry

zonie77
10-15-08, 01:22 AM
Did you check all the things Ranger suggested?

Lebowski
10-15-08, 10:13 AM
I checked the belt, tensioner and surge tank and they all look OK. I also checked the oil. The dipstick was dry. I put in a quart, let it run for a few seconds, shut it off, and checked it again. It was still dry. I added 2 more quarts, let it run for a few seconds, and this time the oil level was almost up to the full line. Could running it 3+ quarts low cause it to overheat?

I just drove it several miles including going 80+ on the interstate and the temp gauge never budged over the halfway mark. There was some exhaust smoke for the first mile or so but then it stopped. I guess I need to do a better job of checking the oil. So how do I get the service engine soon light to go out and also the change oil message to stop, along with the 0% oil life message?

zonie77
10-15-08, 10:19 AM
Change the oil immediately. Overheating it damaged it. Adding some is not what you were supposed to do.


Look at the sticky at the top of this forum and pull your codes, write them down , then clear them. Check online for the descriptions.

Submariner409
10-15-08, 12:40 PM
To reset the oil life monitor, display it in the DIC and hold down INFO RESET for 6 seconds.

Curious that the "Check oil level" never came on. If you get 3 successful start-run cycles without setting an engine code the light should go out.

Playdrv4me
10-15-08, 01:31 PM
Your Oil Life Indicator maxed out because the engine overheated. It is designed to immediately reduce oil life when engine temperature parameters reach a nominal level. Also, please do yourself and stop driving the car now that we've confirmed it is definitely overheating. If you crack the block the repair expense will become a REPLACEMENT expense of the Northstar instead. A successful run on the interstate doesn't rule anything out until you've performed the proper steps to rule out HG failure.

Have the coolant tested for exhaust gases or have a block test done as Ranger suggested. It's not fun but once you have the problem fixed it will not come back short of an improper repair or other issue.

Lebowski
10-15-08, 04:03 PM
I changed the oil and filter and reset the oil life thing to 100%. I went to the sticky to try to get my codes but I don't have any "off" or "warmer" buttons on my '99 STS. Can someone please tell me how to pull the codes on my specific car? What specifically are the "off" and "warmer" buttons? Thanks....

Ranger
10-15-08, 04:48 PM
You where lower than 3 qts. The engine holds 7.5 and the oil drops off the dipstick at 5.5 (2 qts low). If you added 3 qts to get you to the first line, you where probably close to 4 qts low (or 3.5 in the sump). That begs the question, why didn't the CHECK OIL LEVEL message come on? Check the oil level switch in the side of the pan.

See post #2 for pulling the DTC's on your car.
http://www.cadillacforums.com/forums/cadillac-tech-tips/55172-how-pull-codes-got-codes-warning.html

Lebowski
10-15-08, 06:13 PM
I don't know why the Check Oil Level message didn't come on. I just did the DTC scan thing and there were no codes of any kind that appeared. When I was finished I turned off the key, waited a few seconds, and started the engine and the Service Engine Soon light had disappeared. I'll take it for another drive tomorrow and hopefully it will run cool like it did today. I'll also do a better job of checking the oil on a regular basis. Thanks to Ranger and the others for the help....:)

creeker
10-15-08, 06:25 PM
I changed the oil and filter and reset the oil life thing to 100%. I went to the sticky to try to get my codes but I don't have any "off" or "warmer" buttons on my '99 STS. Can someone please tell me how to pull the codes on my specific car? What specifically are the "off" and "warmer" buttons? Thanks....

sorry for stealing your thread,but I would like to know where my off and warmer buttons are too, on my 97 sts, thanks,I'm trying to reprogram my keyless entry.

Submariner409
10-15-08, 07:02 PM
Lebowski, Just to the right of the instrument cluster (DIC) do you have a panel with a rocker and 2 buttons labeled something like " INFO, INFO RESET, and ON/OFF "? (The OFF and WARMER buttons are in the older climate control panel). Turn the key ON but do not start the car. Push the INFO ^ and ON/OFF together and hold until the DIC does a digit proveout and then the message reads CODES?

From here on, INFO is used to toggle back and forth, INFO RESET is "YES" and ON/OFF is "NO".

Press YES. The DIC will ask "all codes?" Press NO. The DIC will ask (and now we get to modules in alphabetical order) ABS? Press YES. The ABS codes (if any) will scroll out. If you miss one you can use the INFO rocker to back up or go forward. After the ABS codes have scrolled, the DIC will ask "clear codes". Press NO. The DIC will scroll to the next module in the alphabet and ask you to verify YES. Repeat the drill. (Pay attention to whether the codes displayed are Current or History.....it's important.)

You can't hurt anything....practice several times until you can scroll to and pull any module you want at any time. You can reset/clear any module code(s) or leave them alone. BUT, do not reset ALL CODES within two or three weeks of an emissions test.....the entire system must settle and display a "READY" signal to the test equipment or you will fail.

There are several sites linked in various threads which decipher codes or you can subscribe your car to www.alldatadiy.com for 1 or 3 years, and get all the service manual plus TSB's, recalls, diagrams, DTC meanings, RPO meanings, you name it.

creeker, look in your owner's manual. The keyless entry process is very different.

Lebowski
10-15-08, 07:17 PM
An emissions test in Kentucky? LOL :D There is no such thing here. After 21 years in California it's quite a nice change, believe me. Anyway, there were no codes of any kind and the only thing in the memory was "IPM-1341-History." The "Service Engine Soon" light is out, there's some fresh Dexcool in the radiator and a couple of gallons of new oil in the crankcase. Thanks for taking the time to help me....:2thumbs:

Ranger
10-15-08, 07:44 PM
sorry for stealing your thread,but I would like to know where my off and warmer buttons are too, on my 97 sts, thanks,I'm trying to reprogram my keyless entry.
I think on your car you press the OFF & PASSENGER WARMER buttons.

creeker
10-15-08, 11:29 PM
I think on your car you press the OFF & PASSENGER WARMER buttons.

Thanks,I managed to reprogram my keyless entry awhile back ( must have been a fluke) it only lasted a few days and then went dead again,I cant seem to reprogram it again.