Vt v6 Overheating Problem... HELP!

[BigBeno]

Hey guys, I have a overheating problem with my vt v6. Ive replaced the heater tap, thermostat, waterpump, radiator cap, overflow bottle and given it a flush. Made sure i bled it properly afterwards. Was running ok, drove today from Bowen to Mackay (bout 200kms) and all was good for 150ks then overheated again. Had the diagnostics thing up on my display and was sitting at around 90 degrees then shot up to 115 and hot alarm started.. Waited for it to cool enough to open the radiator cap with a rag, topped it up with water then kept going with no more problems. I got the car off my brother and he had been having problems with it before hand, but said he had replaced the radiator not that long ago. Anyone got any ideas?? This bloody thing is doing my head in and im out of ideas...

 

[Kdouble]

Have you checked to see if the fans are working?

 

[meady_183]

A water temp sensor providing an inaccurate reading could cause the sudden spikes in the temperature reading. However, as above, I'd be checking the operation of your thermo fans before delving any deeper

 

[Nut Kracker]

If you are driving at highway speeds, the fans do bugger all to cool the engine and shouldn't turn on, as the engine
relies on air flow over the radiator to keep it cool.
The fans will only kick in if there is not enough natural airflow over the radiator. i.e. low speeds.

It sounds like you have really given it a good going over.
I know you have just relaced the thermostat, but maybe it's not opening fully.

Did you have the heater in the hot position, to allow coolant to flow through the heater core when you filled the radiator?

 

[BigBeno]

fans are working fine, kept going for ages after I turned car off on the side of the road.. As for the heater, I know i had it on full when I flushed it and refilled it after doing the thermostat and heater tap... however, i replaced the water pump the other day and dont think i had it on when i refilled it after that. I just reconnected bottom radiator hose and filled it up running and bled it... Silly oversight on my part i guess, Ill try bleeding it again with the heaters on full and let ya's know how it goes.. just started three weeks of night shift though so not sure when i'll get time. cheers guys..
could be a sensor problem too, as it didnt really smell of feel that hot to me when it was doing its freak out