Engine not reaching operating temperature

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Matahoe

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Then it's stuck open a little, your temp should stay very solid, the only time it may fluctuate

Not really seeing the temp fluctuate...it just doesn't get over a certain point with heater fans on. It warms up fine with no heater fans on.

Seeing how it warms up fast with no heater fans on should be proof positive that the thermostat is ok.
 
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Not really seeing the temp fluctuate...it just doesn't get over a certain point with heater fans on. It warms up fine with no heater fans on.

Seeing how it warms up fast with no heater fans on should be proof positive that the thermostat is ok.
I will just say I bet if you pulled the thermostat and put it in some boiling water that it is either just stuck or doesn't close all the way when it cools down.
i could see if it was -20 below or something crazy that maybe that could happen, literally hundreds of thousands of these trucks out there that run with the heaters on full blast in the dead of winter and they heat up just fine other wise they would have changed the thermostats to a lower temp and you would see complaints and questions about it all day long.
but hey if it works for you then great
 
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Matahoe

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I guess I will just order a new housing and thermostat and change it. My suspicion is that it is good. I try to make it a habit to never throw parts at something.
 
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Watch the thermostat housing sizes, there are a couple and I think that depends on whether the water pump is OEM or aftermarket.
 
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Matahoe

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Watch the thermostat housing sizes, there are a couple and I think that depends on whether the water pump is OEM or aftermarket.

Hmm. I'll take a look at the water pump that's on my vehicle. I believe it is a replacement pump that was installed after the factory one went out for the original owner.

If it is aftermarket then that would explain the long heatup times. In that case I'll just get an OE pump and be done with it.
 
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Matahoe

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The coolant temp gauge is a pcm buffered representation of what the engine coolant temperature sensor is telling it. For the sake of troubleshooting you might want to ignore it at first. Its unlikely but it could turn out to be an instrument cluster issue with the stepper motor.

So what I would do is start at step 1 and check the actual temp with a scan tool first. Also make sure hoses are connected to reservoir and heater cores correctly. I found out a while back that the two smaller hoses were hooked up backwards on my coolant recovery tank and it trapped air and a loss of coolant.
 

bottomline2000

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Your still high jacking my thread. Why don't you get in touch with an administrator and move it over into a new one

physically feel the hose coming off the thermostat one you start the truck. If it gets warm immediately you have a stuck themostat. Also, depending on your fan control settings you may have fans activated in recir mode which will hurt your warm up period..
 
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I got the replacement thermostat and housing in the other day. So I removed the one in Tahoe today and put in the new one. Just for grins and giggles I put the old one in a pot of coolant on my stove. It opened up at about 190-195F. The replacement opened at the same temp. Didn't notice any foreign material or corrosion with the old thermostat. I did notice a slight difference in the spring thickness. I also noticed the rate at which they closed was different (because of spring diameter?). That's either a good revision of the previous design or a someone just threw in a substitution which could be hurtful to performance. Time will tell. I'll report back soon. Could be a few days or so until the last bit of air is purged.
 
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bottomline2000

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What kind of coolant are you using and is it pre mix? I run Dexcool mixed with distilled water and my truck starts warming up within a block of leaving my house, but I do have efans..I do not put tap water in my cooling system because of the corrosion it causes.

Sent from my SAMSUNG-SM-T377A using Tapatalk
 

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