2004 GP Coolant Temperature Question

[Chad Gervais]

Greetings, first time poster here. I bought my first vehicle about a month ago. 2004 GP GT1, 190k miles all highway one owner who maintained it perfectly. Ive done extensive internet research and have not found a conclusive answer to my question. on every vehicle i hade driven, rode in, the temperature gauge stays just below the center mark, regardless of ambient temperature and engine load. My GP will stay two lines below center when Im moving but when idling it will go one line past center before going back to one line below center.

I have an ELM327 bluetooth code reader/engine monitor paired with my phone which gives me a realtime temperature reading. Basically when driving on the highway it stays between 185 and 190 degrees. The center line appears to be 210 and the highest ive seen it go is 221 before coming back down.

Im assuming it has a stock 195 t-stat, so is it normal for it to fluctuate between 200 and 220 at idle?

The coolant was flushed last summer, heads were pressure tested, came out fine. The car was making a gurgling sound and losing coolant, the plenum was cracked. It was replaced, and non-dexcool coolant was put in. I was told that dexcool eats plastic parts which caused the plenum failure.

Please forgive me if this seems like a foolish question, I just want to do everything in my power to make this a 300,000 mile (or better) car.

[Durk Diggler]

It's normal, lazy stock fan settings.

[Fivefingerdeathpunch]

Yup, like durk said, its normal.

Stock fan settings are 214 and 226 IIRC, and after these motors heat up and idle, they heat soak, the motor loves to run that warm anyway, its just doing what a 3800 likes to do.

[Chad Gervais]

I appreciate your responses. Ive known many people with GM cars that have really finicky cooling systems. My grandmother had a 94 Olds 88 and an 01 Buick Regal that both ran a notch or two past center, now I realize that the 3800 v6 which is common to all three cars just works that way.

Thanks!