VZ overheating!!!

[MX_Leigh]

hey guys i know this has been done before but the mrs car is overheating at really weird times, only started the other day so i checked on here and bled the radiator and gave it a top up (just with water for now), but again the same problem today, can be driving fine for 20 minutes then all the sudden its getting the engine overheating and check powertrain warning. ive noticed when it does it there is a leak coming from a small plug looking thing around the trans that has a yellow ring around it but i have no idea what it is or what its for. ive attached a picture of where the water is dripping from, not sure if it may be a heater related thing or maybe thermostat? ive only noticed the leak when it overheats. also when it overheats it makes a loud banging noise from the front of the car(maybe the radiator) at first i thought it was one of the fans hitting the radiator every now and then.

circled is the plug and the arrow is pointing towards the front of the car

[impulsive]

could be your radiator cap, check it for obvious signs of wear

[MX_Leigh]

could be your radiator cap, check it for obvious signs of wear

will do mate, would that explain water dripping from that plug near the trans? is it an overflow or something?

[DeanoV6]

vz's run hot 95 to 105 approx deg. water boils at 100 deg so if your cooling system cant pressurize (Has leaks) it will boil at normal temp. Water under pressure raises boiling temp. While the temp gauge is normal at 25% it can be boiling at 30%. Change the radiator cap, look for leaks from thermostat housing gasket, its in the middle of the v at the back of the motor in a s**t of a place. water pumps leak as does the alloy radiator feed pipe above it, Radiators split the tanks.heater taps leak. Its not unusual for you to fix one thing and then it start to leak from some where else. proper pressure test is a good idea. Coolant around the trans is normally thermostat housing gasket.

[crumpledoor#1]

We had the same issue going back a few months. Water was spewing from the front and I could find nothing so I thought it was the over flow tube. It was fine for two weeks and then the water pump crapped out. Changed that and then a week later same overheating problem and found the thermostat crap out. Replaced that and on the way home had the radiator blow. Now the water pump cost me about $70 and an hour of time to replace. The thermostat, given its bitch of a spot, cost me around $350 to have done by a family friend who is a mechanic and has his own business/workshop. Holdens charge upwards of $880 for the same job. The radiator cost me around $140 and an hour of time to fit. All of this work was done and then the problem finally went. Mind you after this we had another warning and due to the overheating it killed the oxygen sensor on the passenger side. Replaced that and the car has been sweet since. Good luck and I hope you can find the issue ASAP.