Avensis overheating

Tomjim

I bought an 08 avensis 1.9 D4D. 110,000 on the clock. cost 4250 at the start of June

All going well until this morning when I noticed the temperature moving up and down, car seemed to be nearly hitting the overheating lines on the gauge but didn't.

I put coolant into it and this seems to have solved the problem (there was very little coolant in the car)

Now I did notice in the last few weeks that the heater didn,t seem to be working very well

is this the head gasket?

RandomUsername

Unfortunately it could be, open the oil cap and take a look in of there's a mayonnaise type residue on the inside of it then it probably is (assuming the car it's in regular use). If not you might just have a coolant leak.
Either way don't let the coolant go low again or you'll have bigger problems

Tomjim

opened the cap - it looks fine, nothing white there

Toyotafanboi

Heaters not working well is a classic symptom of low coolant level.

I wouldn't jump straight to head gasket, you could have a leak anywhere, radiator, water pump, thermostat housing, EGR cooler or any one of a dozen different hoses.

Top it up and keep an eye on it. If it's dropping off again quickly, take it to a garage and get the cooling system pressure tested.

Look for wet stains or a chalky build up on the radiator or below the timing case to see if you have a leak.

punisher5112

Is it not a 2.0

keyboard_cat

Thermostat could be stuck closed? i think you can check them by taking it out and putting it into a cup of hot water

CJhaughey

The big problem is that Toyota gauges are stabilised, once the gauge moves the engine is very hot.
Park over a sheet of paper and see if you have any signs of leaks, is the oil level still good and not low?
Sounds like the coolant was so low the sensor wasn't picking up liquid just vapour and air temps which gave the jumpy readings.
Check your cooling system out properly, this is vital.

Tomjim

just noticed that there is coolant leaking under the car what would this mean

is this a big problem

CJhaughey

Tomjim wrote: »

just noticed that there is coolant leaking under the car what would this mean

is this a big problem

Depends where it is leaking from and how long it has been run low on coolant.
Find out where it is coming from could be water pump seal, radiator, radiator hoses etc.
Get a torch and see where it s dripping from and locate the source of the leak and fix it!
No coolant can lead to a lot of engine damage in short order.

Leonard Hofstadter

CJhaughey wrote: »

The big problem is that Toyota gauges are stabilised, once the gauge moves the engine is very hot.
Park over a sheet of paper and see if you have any signs of leaks, is the oil level still good and not low?
Sounds like the coolant was so low the sensor wasn't picking up liquid just vapour and air temps which gave the jumpy readings.
Check your cooling system out properly, this is vital.

Unfortunately damped temperature gauges are common on many modern cars, as you say once the gauge starts moving you're already in trouble (even if the gauge is not in the red).

Damped temperature gauges were introduced partly because people were complaining that the gauge was moving about all the time and also because a lot of modern cars have mapped controlled thermostats (in other words, they are meant to run cooler under high engine loads so the gauge is damped so that people don't see this happening and think there is something 'wrong' with the engine), but they end up causing more problems than they solve in my opinion (especially in cars without map controlled thermostats).