Aristo Tt Overheating Into Red When At 70mph / Motorway Speeds

[mat_lexus_bournemouth]

I have had my Aristo TT for 2 years and usually drive it around 30-40mph with no problems overheating. When I drive it on weekends somtimes along the motorway the temperature gauge goes to red when reaching speeds of 70mph and stays there and does not drop until I slow down to 30mph back on a normal road. The fan is working and there is water in there.

Should I be using a special coolant as stated in the manual or is normal water ok?

I am now very worried about taking the Aristo up to high speeds as the temperature gauge always goes so hot and into the red!

Please please help. I am thinking that it could be some kind of blockage in the cooling system. The fan is working ok and I have no idea what else could be wrong with it. I even had a look and the coolant plastic holder is bubbling and is very hot indeed! There is no steam or smoke coming out and no problems with the driving of the car or anything, just I am worried about the temperature gauge getting so hot when at the high speeds!

I am still new to the Aristo TT and any help will be truly appreciated.

Thank you very much.

Cheers.

[Dave-Ellen]

You should be using the Toyota red coolant........

I'd trundle off to a garge pronto myself...all is not well.........maybe an airlocck ?airlock even

[Monster-Mat]

check the bottom of the radiator when its running if its cool and the top hot, then you need a new rad

also look at the coolant cap............ ;)

Edited October 15, 2006 by Monster-Mat

[star a]

this is also symptoms of a stuck closed thermostat,

[mat_lexus_bournemouth]

Thank you everyone for your suggestions and help. I did take it to my local garage today and they also think it could be a stuck closed thermostat.

star a is a star! ;)

Soon it will be sorted!

Thanks everyone.

[mat_lexus_bournemouth]

The garage now know that is is definetly not the thermostat but think it could be the radiator. What kind of price am I looking at paying for a new Radiator?

I took the car for another run and it went straight up to the red when I was doing 70mph, I then slowed down to 40mph and it did not even cool down this time. It only cooled when I slowed right down to 20mph.

Does anyone have any other ideas of what could be causing it? If I run my car at idle for half an hour it does not overheat. It is really bothering me as if a car was overheating it would do so at slow and idle speeds more so than at 70mph. Is it somthing to do with the Twin Turbos?

Thanks.

[mat_lexus_bournemouth]

The garage now know that is is definetly not the thermostat but think it could be the radiator. What kind of price am I looking at paying for a new Radiator?

I took the car for another run and it went straight up to the red when I was doing 70mph, I then slowed down to 40mph and it did not even cool down this time. It only cooled when I slowed right down to 20mph.

Does anyone have any other ideas of what could be causing it? If I run my car at idle for half an hour it does not overheat. It is really bothering me as if a car was overheating it would do so at slow and idle speeds more so than at 70mph. Is it somthing to do with the Twin Turbos?

Thanks.

[gsw]

Hi,

Have the garage confirmed its over heating also does it have this fault if you hold the engine at fast idle at around 4000 rpm? Does the temp gauge quickly move in to the red at high speeds and then quickly move down at low speeds then reason i ask is if the motor is over heating right in to the red it wont cool down that quickly if you just slow down as you have less air flow going through the rad.It may be possible that you have some sort of elec fault with the gauge or the sender unit.As for the rad when mine split at the top i was unable to get an aristo one so i fitted one from a gs,it will fit but the position of the top hose will cause it foul the induction pipe as it comes up to the throttle also the fan cowling mounting points will need a little modifying mine been in a few months and causes no problems as for cost i paid £120 for a new one.

[yoshi]

Possible problems :

- the temp gauge is knackered and is misreading (I had this problem in my Mondeo)

- the pump is knackered (easy to check)

[Tony9r]

Well I had the exact same problem with my Daihatsu, which turned out to be the thermostat only opening slightly when hot... so if it's not your thermostat, then you've more than likely got a blockage somewhere :winky:

[chips229]

Hi,

As everyones said..

Blocked Rad.

Sticky thermostat.

Airlock in system.

Water pump worn or broken.

What happens if you put the heater temp on max hot when the temp gauge is high,does that reduce the gauge temp and is the heat from the heater really hot?

Chips.

[mat_lexus_bournemouth]

Thank you all for your help with this one.

You were all right, it was a blocked radiator in the end. Had the radiator and themostat replaced.

Now it is purring like a pussy cat again. Thank you all.

Now I can drive over 40mph without it overheating!

I am now a very happy Lexus Driver again.

[Tony9r]

Thank you all for your help with this one.

You were all right, it was a blocked radiator in the end. Had the radiator and themostat replaced.

Now it is purring like a pussy cat again. Thank you all.

Now I can drive over 40mph without it overheating!

I am now a very happy Lexus Driver again.

Great news Mat, glad you got it sorted :winky: