: overheating , but ez fix?

09-26-07, 12:01 PM
I had problems with my deville overheating last year,
recently I did a bars headgasket fix in a bottle (lol)
the one where you do a flush, drain, fill, water, fill,drain,
and idle it a number of times in 24 hours,

anyways afterwards,
I idled the car in the garage for about a week, few
hours a day,
coolant level was always the same, which was a first for
the car, and the engine temp was always perfect

however when I drive, it might got a bar or 2 above normal temp,
but if I just turn on the heater for a few mins, the temp fixes
it self.

how can it be so sensitive? my cat also may be clogged.

I changed the tstat about 500 miles ago with a oem one.
could that crazy gasket fix in a bottle have messed up
my tstat, or waterpump, or clogged the radiator, or even heater

when I turn on the heat to fix the problem, it takes about a min
to be hot, which is abnormal to me in this car.

I bought a new tstat again, and coolant temp sensor, to see if that
may "fix" things for now


09-26-07, 01:28 PM
We are having the same trouble with our 2000 Seville SLS. Overheating, tried the "fix in a bottle" ran 500 miles great. Then- overheating again! Stopped, cooled, added 1- 1/2 gal water, drove 50 miles, water gone, added 1 1/2 gal again and limped into our driveway- 14 miles later. Replaced thmostat, any ideas? What else?

Brief history to get us to our current overheating problem- I'm just the driver, not a mechanic:
At 76K replaced radiator with NEW by cert. mech/shop- had small crack/leak on bottom, small drip of antifreeze, not a serious problem. Now at 83K it began to idle rough, some steam out of exhaust (white) and stalling. Added bars leak, temp. fix, of course. Tried "block sealer"- similar to above procedure. Good results for 500 mi. Under highway driving conditions 2 hours- begin to heat up, drop back for a time, then heat way up!
That's where I am today- scratching my head and looking at my limited available funds- what to do?
Luv the car, luv to drive it, but need suggestions- trade it in? fix it and keep it? Any help suggestions greatly appreciated!
RL & ML in Illinois

09-26-07, 02:04 PM
Sorry to hear about the problems with your cars. As stated through out these forums miracles in a bottle never work! They are just tempory fixes if that. The problem you guys are having is a sure sign of HG failure. There are alot of threads on here that will help you decide what to do. I have noticed that the repair cost are different from state to state. I heve read as little as 3000 dollars to upwards of 5000 dollars depending the shop. Just make sure they timesert the threads if you decide to get it fixed. Eventually a tech. will shime in and give you more guidance. Good Luck!


09-26-07, 04:18 PM
Thanks for the quick response. We appreciate it!

09-26-07, 07:35 PM
Take the car to have an exhaust gas test done on the coolant. A radiator shop is the best place for this. They will be cheaper and faster.

If it's positive you have a head gasket leak and on these cars it's an expensive fix. The engine gets dropped out the bottom for access.

If it's negative find a good mechanic to diagnose it. Too many bad mechanics out there. It could be as simple as the hoses needing to be retightened at the radiator, or the purge line clogged.

09-26-07, 07:44 PM
I priced out fixing my engine and it is expensive, and I dont know what else I would have to fix at 120k miles,

I have found low mile engines with and without trans for about 1200-1500, which I think would be better and wiser then trying to tear apart my engine and dealing with timeserts etc

09-26-07, 07:59 PM
Chances are that the "fix in a bottle" is clogging almost every part of your cooling system, especially the water pump, thermostat, and radiator. I would flush it out as soon as possible. Since the coolant in your car isn't that old, it may not have exhaust gases in the coolant, wait a couple days, than get it checked for exhaust gases in the coolant. It is better to have the engine rebuilt, and timeserted. If you buy a used engine, even low mileage (hg have failed in as little as 40000 miles) you may be dealing with the same issue again. Timeserts fix the problem for good.

09-26-07, 09:30 PM
Gram2twinz, where are you in Ill.? If it turns out that you do need head gaskets, decide to repair it and are up north, there is a Cadillac tech who once posted and said he will do it for $2200. I can forward you his Name, no. & email if interested.

09-27-07, 03:00 AM
I'd be careful of "low mileage engines" without proof of the mileage. Every engine from a yard has 60,000 miles. Give me a break!!!!!!!!!!!!!!!! If you can check the odometer then OK but how many 60K cars are around going to junkyards?????????????

09-27-07, 09:44 AM
yea, that is true

also i was worried about everything getting clogged

anyways yesterday I changed the tstat again, and the old black rubber gasket was gone,
so maybe the tstat wasnt sealed well in the housing and could never build enough pressure
to open , well maybe until it got way too hot in there.