Richard Hearne

Note to Stevet - hadn'd mentioned it before, but if I switch the heater off (incl air-con) the two fans stop, the car heats up more quickly (surprise, surprise) and back to running efficiently, except I'm all steamed up and have cold passengers. All in all, it points to the systems in the car working incorrectly when its cold. I may of course just be that the thermostat is snafu, releasing cold and warm water for cooling, when its actually not even hot enough.

Hi Guys, thanks for the feedback so far. More details... Open the bonnet, switch the car on an the two radiator fans start up. (not talking about the heater fan in the car) So trying to cool both the engine and air-con coolants, but the car's at 4 degrees (cold). Everything in the car is set to auto mode. The Eco mode light used to be on frequently when low power required, so used the electric motor more frequently, now with the cold system, the Eco light/system stays switched off and uses the engine mostly, which as its cold runs inefficiently. Currently getting about 20mpg (short journeys), however before it got cold was doing approx 40mpg. On longer journeys when the system gets 'hot' it all start to work as in the summer (before cold weather), but as soon as I go down a long hill, or have been using electric power for a bit the engine cools down and it all stops working the way I would expect it to, and starts using more fuel again.

Hi, I have a new GS300h F Sport (5k miles) and have the following problem which my local agent won't acknowledge. As soon as I switch the car on - the engine and air-con fans start up, even when the engine is freezing cold, as a result the engine fails to warm up properly and my mpg drops thru the floor. All the electronics relating to how the engine/hybrid system works seem to be related to the engine temp, so in my case don't work very well. Once the engine is hot, everything seems to work properly, good(ish) mpg etc. However, if I go down a long hill in overrun, the engine temp drops and everything stops working again. Agent says this is how they work, which I feel is a feeble excuse. In all my years of motoring (in cars with electric fans) the fans have never switched on until the engine or air-con temp required cooling. Has anybody has a similar experience and can offer an explanation/cure.