Does this sound like a thermostat issue? - update, nope.

[g300d]

As I posted in a few other threads, I'm chasing a higher than normal Ktemp situation (but not overheating or even enought to move the analog gauge) on the 3.0.

Normal observed is 92-93, brief bursts to 96-97, sometimes I go mid 80's on steady highway cruise.

Lately it's 96-99, that goes down to 86-87, then back to 96-99.

I stood infront of the car with the hood up and observed this:

From 96-99, temps would start to go down and the engine fan is obviously pulling air through the rad. If you put your hand behind the fan the air flow is steady and hot.

While this is happening, the airflow is steady, but gets less hot. Ktemps reflect this.

At mid 80's the airflow is still steady. After a while Ktemps start to go up.

But...even as it gets to 90 and above,the airflow is not hot. It can get all the way to 99 and the airflow is still lukewarm. Sometimes you can even feel the fan decouple and the Ktemp is still 96-99.

Then all of a sudden, the air behind the fan gets hot, and then you can see Ktemps go down.

I think the Ktemp goes up because the thermostat keeps coolant from the radiator. The up and down is the thermostat cycling differently from before.

That's my theory now. But I've never come across any other BMW owners that have experienced the same. Mostly people having 'stats stuck open giving lower than normal temps.

What do you guys think?

Update: replaced 'stat, still dont have my old 92-93 deg ave temps. Now moving on to coolant system pressure testing to look for leaks and other possible problems.