Where should the temperature gauge be registering at normal operating temperature?

2004 PONTIAC GRAND PRIX
105,000 MILES • 3.8L • V6 • TURBO • 2WD • AUTOMATIC
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ALAN POSEY
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it is running a bit over half way. i have replaced both head gaskets, the radiator, the water pump, thermostat, and temperature sensor. i checked the cooling fans and they seem to be working fine. i have flushed the coolant system three times with prestone flush and removed block drain and refilled with fresh antifreeze, distilled water, and a corrosion inhibitor.. it builds up pressure on radiator hoses quickly upon a cold start, but i have checked for bubbles in the coolant and there are none. it's about 80 degrees outside and after a short drive the engine seems quite hot to me. is this normal?
Apr 8, 2021 at 1:24 PM
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ASEMASTER6371
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Good afternoon,

When you had the heads off, did you have them checked for being warped or cracks?

You may still have a head gasket issue. The fact it builds up pressure quickly tells me that. You need to have a leak down test done to verify. You also should have replaced all the head bolts during the repair.

https://www.2carpros.com/articles/head-gasket-blown-test

Roy

Apr 8, 2021 at 3:59 PM
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ALAN POSEY
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They are not warped or cracked, the car has never been run hot. it sat for about 2 years and i bought a complete engine gasket set and tore it down to replace the intake gaskets and i figured i would go ahead and replace the head gaskets and valve seals while i was there, and since i had the gaskets.. Also i picked up new head and rocker bolts and cleaned all surfaces thoroughly, and torqued every bolt to specs. this is why i am puzzled.
Apr 8, 2021 at 5:05 PM
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ASEMASTER6371
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Okay, what temperature thermostat did you install? It should be a 195.

You will need a scan tool to verify the temperature as well to see what the actual reading the coolant sensor is sending.

https://www.2carpros.com/articles/how-a-coolant-temperature-sensor-works

https://www.2carpros.com/articles/coolant-temperature-sensor-cts-replacement

Roy

Apr 8, 2021 at 5:17 PM