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I bought a 2006 trailblazer ext with the inline 6 last week. Drove fine on test drive. I got off the highway on the way home and it died when i stopped at every light. I figured it was the throttle body, so I cleaned it. Very dirty.
drove to work today, only issue was that the temp gauge didn’t climb above 1/4. I figured that the thermostat needs replacing. Drove it home. Stalled again at the same place and every time I stopped. I also noticed that the temp gauge has climbed to halfway (normal). Obviously hotter outside after work vs the morning. A/c was not on the second time. It was the first time, but no refrigerant, so the compressor wasn’t running. No engine light. Stored code p0128 for thermostat below operating range.

could the thermostat cause my stalling issues?
 

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Depends.... typically a low temperature opening thermostat at a certain level will keep the computer from getting into Closed Loop.
Not sure if what you read is what you are actually getting though. Some CTSs are specifically for the ECM ... and some onky feed info to either the dash or the ECM ... in that case you may have two coolant temperature sensors, one for each.

MOST default values for a CTS come out to falsely sending spoofed information to the ECM that the coolant is -45° F ... highly unlikely as the northern hemisphere is in full-blown summer (I'll assume so anyway).

What you might check is if there is actually any coolant in the engine and radiator ... not just the recovery tank. If a coolant temperature sensor isn't covered in coolant, it will give a false flag.

These are basic things to consider, but we have to make sure that the minimum requirements are in place before looking for the real problem.
 

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Thank you for the reply. Finally got a CEL this morning. Got 5 codes. P0128 p0300 p0017 pp365 p0446
Going to swap out the thermostat and the cam position sensor and go from there.
 

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Do repairs one at a time!

Sometimes they can cross-communicate and mess with the ECM and give you too many false codes. The ECM "needs to see" a clear, green board with all sensors functioning and then it goes in Drive Cycles - which is too complicated to discuss here.

If you want, I can send you a link to a neat book - 56 page owner's manual really for a really cheap-o scanner. I swear, there is no Chinglese and oddball words and syntax - It's really written by someone who speaks English better that you and I do!

Let me know - it's a downloadable PDF and it's free. Once you read it - you'll have a much deeper appreciation for what the auto engineers are up against with rules that change on a daily basis and "Pi in the sky" (see what I did there?) dreams of some cubicle dweller with a sliderule and an idea.

I'd change the thermostat first - and you'll find it's an ASSEMBLY with a built-on neck and the thermostat is captive.

BTW---> this cooling system kinda works backwards!

Check out the thermostat housing and try to figger it out for yourself. If you 'get it' you'll be yards ahead of a lot of people here - believe me!
 

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Cam shaft position sensor made 2 codes go away, but it’s still stalling. Keeps running if I drive with 2 feet. Going to try to find time to replace the thermostat this weekend.
Wouldn’t turn down free learning resources.
Cooling system works backwards? How so?
It seems like all of the videos on YouTube show taking the alternator and suck out, yet people talk about going through the fender. Is it as easy as they say?
 

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Ok ya got me in bed now, so I may fall asleep on ya at any moment.... here goes...............

The thermostat controls the coolant coming from the cool side of the radiator... IN to the engine on the lower side behind the alternator...which is pretty easy for me to replace from under the hood. (2 birds, 1 stone)

I didn't believe that the cooling was designed to work like that... but I confirmed it twice. I should state right here that I'm not 100% sure that my water pump is turning the right way either.

So far......... no troubles..... but that can change at any point in time.
 
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