[s346k]

eh. v6 ftl

[Petrol Head]

Originally Posted by GTIanZ28

I’ve been trying to replace my thermostat on the LGX for 3 days now. I should have taken a picture.

In order to get to the thermostat on the LGX you have to remove the entire intake system to include the intake manifold. The thermostat is in between the heads in the valley. This is where the problems begin. There is a metal return line coming off of the block that is directly above one of the thermostat bolts. There is zero room to get a wrench or socket to the bolt. I’ve bought every tool I could find that might work.

I’m at a complete loss at this point about what I should do (besides taking it to the mechanics).

Not to make light of your situation but that right there is why us old school guys are still mad GM quit building the old 3800 231 and replaced it with the L-series 3.6 blocks. There was nothing wrong with that engine and it was a piece of cake to replace anything.

[Badmojo]

I've had a factory thermostat fail and cause overheating at the track on my LT4. It happens.

[GTIanZ28]

Follow up on the LGX thermostat issue. Managed to get the 2nd bolt out with a 10mm wrench that we hammered to a 30 or so degree angle at the end. Worked perfectly actually.

But, the thermostat won’t clear the metal overflow return lines that are coming out of the heads. I’m sure those can be removed (I don’t know how to do that).

Pulled the old thermostat up enough to compress the spring a few times and then re-assembled everything. It unstuck the thermostat for now and everything is back to normal.

[onkeystime@yahoo.com]

Same thing with my 2017. Fan stayed on. Temp gauge at C. Took to dealer. Said he had 8 Camaros similar years all with same issue in the last 2 weeks. Said all have similar odo. So it seems this thermostat goes bad around 40,000.

[redcoats1976]

had this happen to my old pontiac solstice,it was the thermostat.

[ctrlz]

Originally Posted by onkeystime@yahoo.com

So it seems this thermostat goes bad around 40,000.

I would be shocked if thermostats starting failing with regularity on any car. Typically a highly reliable, simple component. Very easy to monitor its behavior with the temp gauge present on every vehicle I've driven for the past 30 years. And the performance of your heater serves as a secondary "monitor."
I drive my cars to ~150k miles. On some I never replaced the 'stat. On some I did it once. Worst experience was a 2004 Audi A4 1.8T (an engine known to run hot). Thermostat was housed in plastic and would fail, as would the coil packs (also plastic). Three thermostats and maybe 10 coil packs in 40k miles. Shocking how poor the mechanicals were on that car, but my wife still gloats about the comfy interior. I have permanent audi-phobia.

[cellsafemode]

my thermostat has failed in the open position at about 40k miles. (though i've had it since feb 2016)

Still dragging my feet on replacing it (i have a new one and a new temp sensor waiting in the garage )..

You can tell if your t-stat is stuck open or closed when the temp sensor gauge is reading nothing by checking your oil temp. If the oil temp is stuck at low to normal temps while idling...then the t-stat is stuck open and the worst you're gonna do is run your electric fan way too much and not have functional AC or very hot air.

Clearing the codes works temporarily but eventually the low temp behavior will trigger again.

It's annoying that it doesn't combine temp readings with the oil temp sensor when deciding if it should go into it's fallback mode of disabling the AC and runnning the fan like you're overheating.

Anyway, replacing this t-stat is going to be annoying so ...i'll probably do mine when i'm super bored. Not paying a grand for some dealer to do that nonsense though.

[ctrlz]

Originally Posted by cellsafemode

Anyway, replacing this t-stat is going to be annoying so ...i'll probably do mine when i'm super bored. Not paying a grand for some dealer to do that nonsense though.

I was looking this over in the repair manual. Looks like the official procedure for the v8 involves draining the coolant and removing the water pump, as the 'stat housing is bolted to the side of the pump. But you might be able to pull the housing without removing the whole pump. I can't tell and it's 20 degrees out. I'll look at my car when it's back in the garage.