On the way to uni today i noticed my temp gague was reading 3/4 instead of its usal halfway on my car. Pulled over checked everythign was right, enough water, no visible leaks or drips. Had an exam on so had to keep going, as a precaution when a car overheats i turn on the heater to max and crank the fan, went back down to halfway, turned it off back to 3/4. Pulled over at the next servo resevior water was at ambient but thermo fans were no going, in traffic i couldnt hear the fans and it would overheat. Even with heater on in traffic overheating, once in motion there were no problems as long as heater was on. From This i have concluded it must be thermo fans or a combination of thermo fans, and coolant.

sounds like your fans might be playing up...

did u just check the resivior? i think itd be better if you check the radiator when she's cold....

Already Did that after my exam.

The overheating problem with my KR turned out to be the water pump, which was leaking down the side of the block. Has your car still got the original pump? If so, I'd get it checked out, cause they apparently have a cavitation problem that gets worse as they age. If you're losing a lot of coolant, it's likely that this is your problem. If it's not too much, then it may be your thermo fans. Can you smell hot coolant when you open the bonnet?

still has original pump, however about 2000km my mechanic said she was good and didnt need changing, couldnt smell coolant, but pump is on my mind.

my water pump packed up a few months back...but there was a visible leak on the that side of the motor.

u may need to take the front left wheel off, and check around the crank sprocket. thats where youll see any coolant as it settles there.

if not, then id say its something to do with your fans....in fact id say thats the problem now. because if you had a leak and you were running low on water, your fans would be working alot more to compensate for the loss of coolant...

In my KS, when I had cooling system problems it as my thermostat.... started with the temp gauge going sky high, and the radaitor fans just **** emself.... literlually snaped off the shroud.

Also another thing.... check the sensor in teh bottom of the radiator....

Yeah i reckon thermostate too.. Most common over heating problem..

Easy test is to feel the radiator hoses when the car starts to get to hot..(over heating as you say)..

When you feel the hoses they need to be the same or similar temperatures top and bottom hoses.. If there is a differant then there is a problem.. If the thermostate isnt opening when it should the top hose will be cold and the bottom really warm.. if the bottom is only just cooler then the top then you will find its water pump not pumping properly.. Also when the water pumps go they usually leaks or gets real noisy in the bearings..

Is the engine making any new noises laterly..???

yeah the radiator could actually just be going, mine was like that once and i took it in to get checked and they said the inside were screwed

may as well add my story to this thread.

My v6 TS wagon (200000km) temp guage normally sits at 45% mark.
one day i noticed it sitting much higher in temperature and the temperature guage reading is quite sensitive to vehicle speed. (ie driving 70kmh+ temp drops quickly, driving 40kmh- temp rises quickly.)
check coolant levels- levels low.
add 1.5L -same happens a week later.

notice coolant under car when parked sometimes- but not consistent -couldn't see obvious leak while running.
replaced radiator cap and thermostat (88°C)- both cheap parts (~$30-$40 total). old thermostat looked a hundred years old and was stuck in the open position. (means engine was running too cool before problems started?).
this did not fix problem- still losing coolant and temp guage sitting on 55% most of the time.
have since noticed coolant drops falling down on the RHS engine cross-member just below the bottom large "pulley" of the engine. couldn't see well where exactly the leak originated -probably the water pump above (yay..$$$) -will inspect more closely this weekend.

a cooling system that doesn't hold pressure (ie leaks) probably also doesn't allow a proper negative pressure to form in the cooling system as it cools to draw back coolant in the over-flow bottle. I had noticed a fair bit of coolant in the overflow bottle on occassion.

i will document here what happens and cost of repairs etc here to help other poor chumps reading this troubleshoot similar problems they might be having.

Sounds very like your water pump.
Rob

still sounds simmilar to when mine done the thermostat

turned out to be the water pump leaking, actually the morning i went to take the car in to get a quote, there was a huge pool of water under the car.
the car had just done 200,000km a week before, so got the timing belt done and got some new pulley/pulley seals thrown in too cos it was slowly leaking oil from there. all up it cost me 1k :shock:
it could have been worse, if i had gotten the timing belt done before the pump started leaking then it could have cost a few hundred more.

anyway, she's all happy now. my wallet is thinner, but that's life with a 10yr old car; some big ticket items are ripe to go wrong.
still, its much cheaper than having a new car (~5 times cost of a TS magna), that you have to insure properly (i only have RAC 3rd party, saving $400+ per year) and new cars you have to get regular ripoff servicing twice a year to keep the warranty. (~$500 per year on average, i do my own oil changes and servicing and get things fixed as they come).

it's important to rationalise expensive car repairs to avoid getting too pi55ed off!

Yeah i reckon thermostate too.. Most common over heating problem..

Easy test is to feel the radiator hoses when the car starts to get to hot..(over heating as you say)..

When you feel the hoses they need to be the same or similar temperatures top and bottom hoses.. If there is a differant then there is a problem.. If the thermostate isnt opening when it should the top hose will be cold and the bottom really warm.. if the bottom is only just cooler then the top then you will find its water pump not pumping properly.. Also when the water pumps go they usually leaks or gets real noisy in the bearings..

Is the engine making any new noises laterly..???

shouldn't the lower hose be slightly cooler than the top...
considering thats where the coolant is pumped into the engine from(as long as the radiator is doing its job...)
and the top hose should be warmer(where the coolant comes out of the engine)
pfft i could be wrong but this is how mine is.. and mine has no problems all...

reason i say this is.. water travelling from radiator --> engine, water needs to be cool so that it can absorb engine heat.. and water traveling from engine --> radiator, water will be warm as it has just absorbed engine heat.. radiator cools water before running into engine.. if it didn't what would be the point?

oh and my water pump is fine too...

i am talking slightly cooler.. not like one is cold and the other is hot..

Fan control solenoid something or other went on mine *shrugs*.