Overheating + Fan Not Coming On

[Tru]

Has anyone had problems with their RX300 overheating? Mine is a 2000 less than 100 thousand miles. We are having problems with the car overheating only after we have driven a ways lets say 20 miles or more. We had the waterpump, timing belt, thermostat, radiator temperature sensor (something like that) replaced. No problems that would indicate a blown head gasket. The fan does not coming does anyone have any ideas what could be causing this?

[ihpj]

If you recently had the work done, then I would take it back to the garage and explain the problem as something might be amiss linked to the work done. I wouldn't worry trying to fault find blind like this.

Take it back to the garage and see what they say.

[J3NKO]

Check your radiator has coolant in. I'm gonna bet the garage have drained your rad to do the work and forgotten to put fluid back in...

The fans won't come on if the rad isn't hot and the rad won't get hot if its bone dry!

Whilst the car is cold, pop the bonnet, and open the radiator cap. Look inside and fluid should be over the top of the rad elements and maybe even some coolant in your overflow reservoir (if the RX300 has one). If you can't see any and you don't have any coolant at home, fill the radiator up with tap water as a VERY short term measure and take it straight to the garage where they can drain it and put OEM spec coolant in.

If there is coolant, the next check would be the thermostat if it were mine.

If its the former, get them to sort it free of charge and then sack them. Take it somewhere else next time because thats a schoolboy error!

[J3NKO]

Well????

I'm on the edge of my seat here?

[MURPHYBEAR]

Hi

I've got a small overheating problem. When the car is stationary, the temp gauge rises towards the top of the scale.

Mine has four marks and the pointer usually sits on the lower middle mark when going along. When stopped the pointer rises to the top mark below the HOT and stays there. If you put your hand on the top hose it's not unpleasantly hot, certainly not boiling and no overheating smell.

At this temperature one of the fans goes into overdrive but not the other. I spoke to Lexus to get some idea of the temperatures shown by the gauge (I haven't found out!!) but I'm guessing HOT is 90 something C and COLD is 80 something C and the gauge shows about 10 degree Centigrade range.

It might be a faulty temperature sensor or a disconnection somewhere /bad joint.

Both fans run.

Any ideas/contributions please. I'm having the Cambelt changed next Wednesday and a new water pump and tensioner at a local garage. We'll see what happens.

Murphy bear

[MURPHYBEAR]

Hello everyone

Work done: cam belt , tensioner, water pump, new rollers, and on the advice of the mechanic - new spark plugs as they are hard to get to. Vehicle had done 113,000 miles . Coolant had slime in it before and this was replaced when work done. I've had no problems since with temperature. The gauge pointer sits on the lower middle division - I must have had a low water level and the changes have cured the problem. I have done 1800 miles and the engine runs beautifully. The top up bottle was full to above the line when overheating so possibly there was a blockage in the overflow line but I did pull the pipe off at the radiator end and water ran out from the open end.

Hope this helps

Murphybear