hello all new here. 20+years repair exp. my 96 century 3.1 limited has been running cold lately. still has heat, still warms, but wont go past the 1/4 mark on the guage. so with only having 55,000 on it i figured i must have a sticky thermo.

i ran out to auto zone and picked one up, drained about a gallon of antifreeze and set out to do a quick 5 minute thermo swap.......and THEN i realized it was located under the entire throttle body, and above the exhaust manifold and intake..........my question is.......is there ANY humanly possible way to remove the housing and swap the thermo without costing me 3 hours of work to do so?

i even went out and bought the haynes manual and it mentions NOTHING about the throttle body or manifold being in the way, only shows the 3800 pictures and only says like 3 lines about the 3.1


any help would be appreciated because i've never in my life seen a thermostat setup this stupid ....and that's after 20 years of working on engines :-p

 

My car, with the 3100 LG8 usually stays around the 1/4 mark around this time of year. At least when its not idling. Unless it stays around 1/4 after idling for a while, I would consider that fairly normal.

I think there was a video posted here yesterday about how to change the thermostat on a 3100. I'll see if I can find it for you.

 

Here it is. Its for the 3400. I'm not sure how much different yours is compared to this.

 

Hi, I'm on the other thread with my temperature gauge problem, and one of the guys sent me the video on how to change the thermostat. You're right, it's the pits on where they put it. He explains it pretty well, tho, I admit, but it is not an easy thing to do. Anyhow, what would be the normal reading for the gauge to show it? 1/4 mark, 1/2 mark, or 3/4 mark? I cleaned the connections on the sending unit itself, and the dash gauge slowly, very slowly, goes up to the 1/4 mark.

I know the coolant is hot, after a drive, I get plently of heat from the heater inside the car. Anyhow, go on my thread, and view the video. Ed

 

Like I said, when its colder out, and driving around, my car usually stays around 1/4. After being parked and idling for a while, it will go up. Mine usually sits around half, or a little above, after idling for around 15 minutes.

 

If the thermostat is stuck in the open position, wouldn't the gauge just show a 1/4 reading mark? And even tho low, you still would get heat in the car.

Which thermostat relacement should one get? the 180 degree, or the 195 degree?

 

mine just sits at the 1/4 mark when im driving. summer or winter. if i idle in traffic it starts to rise. then when i move it dropps again. i get good heat, coolant gets warm but never to normal temp. gonna flush the radiator today. coolant looks VERY old and is the old style red stuff, probably OEM and was never changed. then im gonna take a crack at the thermo. its like 64* out today so its a good of a day as any haha.

 

It's a wise move to get rid of the red Dexcool in the cooling system. Try googling buick intake plenum problems. Better move is to replace coolant with regular green anti freeze. In the old days everybody used a 180 degree thermostat. Today the newer engines require a 195 degree thermostat for the following reasons, the higher temp of the engine keeps the hydrocarbons low and permits more complete combustion. This is important in states that have strict emission requirements in order to pass inspection.

 

mine sat 1/3 to 3/8 all the time unless I get rush hour traffic. Then it pretty much stands straight up till I hit max heater temps and put it from windshield to floor mode. then it drops in a few seconds to get back down again. Also realized we have the series III 3100. I believe it's the same location for your series II. your engine look like this?

 

Looks like the 2.8 was also similar.