96 century limited stupid thermostat
 

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?

http://www.stationwagonforums.com/fo...9/dscf1891.jpg

Looks like the 2.8 was also similar.

http://thebaron.110mb.com/mpfi/instal31.jpg

Need to stop hitting submit and then getting another idea. I also want to piggyback on the death cool orange fluid. If left in the engine long enough it be comes acidic. 100,000 fluid change my a... and yes that random wrench in the video looks like the best option. Taking the entire manifold off makes the T/Stat 99% easier, but you add the fun of the intake manifold, gaskets and remembering the pushrod order to the mix. There is also the option of the crossover exhaust piece removal but there are gaskets to that as well.

I may be wrong, but I think the 1996 has the L82.

Looks like it is a L82. Next time I go to the J yard I will look at those cars with those 3.1 I posted to see what years they were.

According to wikipedia, the only 3.1 that was available for that gen was the L82. 1989-1993 had the 3.3, and 1994+ had the L82..

The one you posted was the LH0, and was found in:

• 1988–1991 Pontiac 6000
  
• 1990 Chevrolet Celebrity
  
• mid 1989–1993 Pontiac Grand Prix
  
• mid 1989–mid 1993 Oldsmobile Cutlass Supreme
  
• mid 1989–1993 Buick Regal
  
• 1990–1993 Chevrolet Beretta
  
• 1990–1994 Chevrolet Lumina
  
• 1990–1994 Chevrolet Cavalier
  
• 1991–1994 Pontiac Sunbird
  

Yeah same article. Another link suggest it had a different 3.1 engine as well as the 2.8 as an option. I trust the wiki more(lol) cause I used that to seek 3400 parts.

My engine reads: 3100 SF1 V/6. Can I use a multitester (multimeter) to check the connections on the sending unit to use if that is the problem? And if so, what do I connect? Ed

I was never good @ electric trouble shooting.

Yes, changing a thermostat is a hassle. Maybe when it gets warmer in the Spring, I'll take a go at it. Repair shops want a bundle to do the job. Oh how I long for days gone by, when it was so simple to a job like that.

I like my 96 Century, it rides nice, good mileage, good reliabilty repair record. Why those engineers designed such an engine to make simple maintenance jobs difficult is beyond me. Ed

Hi Guys, Happy Thanksgiving !
Before I learned why some things were done the way they were I too had bad things to say about what some engineers did. But, I learned it's not always their fault. The "defect" in the manufacturing lies in the "bean counter dept". When an engineer submits a plan , the bean counter says we can save 2 cents here and 3 cents there so how it gets fixed when it leaves here is not our concern cut this , cut that it will save us 50 cents per vehicle. Multiply that times the number of vehicles produced and the bean counter gets to keep his job. Don't forget there are some engineers that like to repair their own vehicles and they know darn well it's wrong, but there isn't much they can do about it. I had the opportunity to take classes through the local GM plant and watch the dash assembled from the inside out. Pretty easy, but don't try to get at anything from the the passenger compartment side. Time to get off my soapbox.

Yeah the resistors in the gauges and the sway bars were blatant disregard. If you ever get a chance, grab the rear sway and shake it.

How often was coolant changed? I still say it could be scale build up on the sensor. If the car isn't overheating and sending engine stays cold too long pending codes it could wait.

On another site, a guy suggested running a wire from the green slot on the connector plug that goes into the sensor to a ground on the engine. With ignition switch ON, but engine off, if the dash temp. gauge shoots all the way up, it means the wiring and gauge are O.K.,

Which means either the sensor is bad, or the thermostat isn't functioning properly. Ed

Hi, On the previous thread, I couln't get to see the video. It was in Polish, and I didn't know which site to click on. Please show me the correct one. Ed