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Thermostat in am '03 Grand Prix 3.8L

I now know I need to change the thermostat. Upper hose is hard and hot. Now, I have not had thermostat issues in decades, so, what I am seeing, confuses me.

I have a temp gauge. Around Bugtussle, car does not warm up because I do not go far enough. This last few days I was out on the highway, car warms up to the normal spot. Get to the city and the gauge moves from normal up to the 100°C, starts slowly creeping higher. It has never done this before. I turn off the AC, turn on the heat, bring the temp down. Drive on the highway, temp stays normal, maybe a half notch higher. Slow down in bugtussle and the gauge starts creeping up again. 

Just now, four blocks to the liquor store, 4 back, it starts showing hotter than ever for that distance. Fans are coming on. Upper hose hard and hot.

Yeah, but, if the thermostat is not opening, why am I not over heating all the time? Is there enough airflow on the highway to keep it cool enough?

I will go over to Ad-Vic Bearing Auto Parts and buy a thermostat from the guy that owned the car before me. This is a small town.

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Re: Thermostat in am '03 Grand Prix 3.8L

PS: What does the tailpipe look like? I mean, if you play proctologist, and stick your finger in, is there any residue or anything? When the car is running, if you stand by the tailpipe, is there any smell of antifreeze, or a kind of hollow "glug-glug" noise?

 

You can tell a lot about a car by the old....errr....tailpipe probe. No wonder it's so popular with those little green men from outer space! (If only it were more popular with the green women!)

Message 16 of 52
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Re: Thermostat in am '03 Grand Prix 3.8L

Aren't you just a ray of sunshine.

I choose not to hop on board the "It's gonna die" train. Let's solve one problem at a time. Drain, flush, fill, will solve a lot of problems. Coolant just got to the end of its lifespan, just, like, that.

No glug glug, more of a ladylike gentle sipping. No white clouds following me. 

Message 17 of 52
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Re: Thermostat in am '03 Grand Prix 3.8L

Oh, I agree, Elmwinkle. No need to get paranoid just because of what may indeed be a minor problem- but me? I just like to have an idea of what's going on with my vehicles, so things don't sneak up on me.

 

Kinda like a neighbor of mine. He comes by one day to show me the little Turdcell he just got off'a CL. I said "Is it me, or do I smell coolant?". I knew right then that the head gasket was gone. Took a month or two before he came and started telling me that the car was starting to overheat, etc.

 

Kinda worked out for the best though. I helped him replace the head gasket, and it gave him so much confidence, that he opened a shop!

 

But yeah, the "white clouds of smoke" and "coolant in the oil" are pretty rare on modern cars even with blown gaskets, unless the person keeps driving 'em after they blow, and really ruins 'em. Last twenty-something years, I think I've seen one car with a blown heady that actually coolant in the oil.

 

If i do seem a little paranoid, it's 'cause anything GM made within the last 30 years, is pretty much guaranteed to have a head gasket issue sooner or later. Hopefully it's just like you said, and by catching it right away, you can avoid the bigger problem.

 

Modern cars: They make it so you can go 100K miles before changing the spark plugs...but head gaskets and automatic transmissions don't last that long.

Message 18 of 52
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Re: Thermostat in am '03 Grand Prix 3.8L


@legitimate_bidder wrote:

 

Modern cars: They make it so you can go 100K miles before changing the spark plugs...but head gaskets and automatic transmissions don't last that long.


Yea but it's easier to replace the transmission than the plugs.

Message 19 of 52
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Re: Thermostat in am '03 Grand Prix 3.8L

Do you guys, like, do funerals, you know, to bring the mood down?

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Re: Thermostat in am '03 Grand Prix 3.8L

@mr.elmwood


@mr.elmwood wrote:

Do you guys, like, do funerals, you know, to bring the mood down?


We gather here this day, 

with a heavy heart.

 

To pay our last respects.

to "Old Rusty"

 

300,000 miles she ran.

But her race is over.

 

Through ice and snow,

fog of night,

She never failed.

 

The things that happened

in the back seat,

she would never tell...

 

In the end her head gasket went bad.

and the water... looked like mud.

 

All for the want of a radiator gasket ...

Message 22 of 52
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Re: Thermostat in am '03 Grand Prix 3.8L

I am GLAD to see you back on the board.Bruce.

Message 23 of 52
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Re: Thermostat in am '03 Grand Prix 3.8L

runny chilli-now thats funny-issue likely caused from neglect,a high possibility is fins on water pump near gone(cant circulate enough coolant-or chilli)

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Re: Thermostat in am '03 Grand Prix 3.8L


@cepclpi_ecwztwxzvc wrote:

runny chilli-now thats funny-issue likely caused from neglect,a high possibility is fins on water pump near gone(cant circulate enough coolant-or chilli)


That's what would scare me. If the previous owner neglected something as obvious and major as the cooling system....you can bet everything else was neglected too. And with these aluminum-head injuns not being tolerant of ANY heat, the least little flaw in the cooling system can prove fatal- and chunky-style coolant is far from a "little" flaw!

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Re: Thermostat in am '03 Grand Prix 3.8L

Just in case my last post upset Mr. E.:

 

1f9856972f0419079900939279ab9653

Message 26 of 52
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Re: Thermostat in am '03 Grand Prix 3.8L

Chunky style antifreeze is bad news. My BIL god rest his sole, was by no means a mechanic. He came to me one day and asked me to look at the heater in his Scout, said it quit blowing heat. Upon inspection I found the chunky style antifreeze. I asked him when the last time it was changed? He said ten years ago when he first bought the Scout. I asked him why he never changed it in ten years he said he didn't think he had to because it said permanent on the bottle!  Can't make it up!

Message 27 of 52
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Re: Thermostat in am '03 Grand Prix 3.8L

Mistake is on me. I bought the car with low enough mileage that I assumed original fluid. I bet it is not. Someone changed it, did a poor job. I caught it in time. 

We shall see, later this week. dum-de-dum-dum

Message 28 of 52
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Re: Thermostat in am '03 Grand Prix 3.8L

You were lured by the prospect of low mileage but ignored the downfall of infrequent use.

Message 29 of 52
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Re: Thermostat in am '03 Grand Prix 3.8L


@atikovi wrote:

You were lured by the prospect of low mileage but ignored the downfall of infrequent use.


That's why I NEVER buy low-mileage older vee-hickles. If it wasn't driven, and maintained by someone who knows how to get those miles out of it....I don't want it.

 

I hate to be the eternal pessimist, but if i were Mr. E., after changing the fluid, if all seems well, I would sell that car, while I still could with a clear conscience. I've seen enough with those GM cars over the years...one hiccup is all it takes. The results may not show up for months...but the damage is already done. 

 

Get it flushed out now and good coolant put in, and any problems might not show up until next summer or the next trip to the States..... EVERY aluminum GM 6 cylinder from the mid 80's to...uh...now...is a ticking time bomb.  And if she's been overheated in the past, not only will the head gasket be an issue, but the tranny, too. Hauling junk like i used to, it was always the same scenario: Clean GM 6cyl- often with well less than 100K miles...no obvious damage....wouldn't know it if the owner didn't say it: Blown head gasket. Usually starts with a bad fan sensor.

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