Topic: 4age turbo over heated

Hi Guys
So i took the car out and when coming home a had a few pulls mostly held it down in 4th for some time.
did this like 3 to 4 times .

So got to a garage to fill fuel there was nothing but left the car on,
started to drive it home then saw the heat gauge fuel , drove it a little , rolled it a little and the gauge went back to half and drove it normal home,

Now what could cause this?
1.Cooler to close the radiator?
2.Too much or too little timing?
3.Turbo mani giving off to much heat?
4.Could it be bad circulation of the water system?
I am running a mix of water and anti freeze but more water.

What can i do to fix it?
i have not seen it over heat any other time.

I started the car up today and drove it.
noticed now that a low revs its pinging/pinking?
Response or when taking off is not so easy.

Could this be the plugs?
Or the map went off?
Maybe some oil went into the vac lines?
ODR Tuned - 114hp
2001 Tazz(4age 16v stage1 conversion)-90wKw and 141NM- Auto TriX
Speed Shop = 137.4BHP AT 7500RPM and 147.3NM
RunX RSi old spec 128kw ATW Rally cross and Auto Trix
2008 Polo TDi 9N3 74kw 240nm