Tempreature gauge

[Focus2k6]

Hi,

sorry if this is posted in wrong place. 

I have ford focus petrol 2006 1.6 ghia, when my car is stationary for 10-15 mins the gauge will increase to optimum tempreature (about 88° and stays there) but when I travel around in the car the temp drops slowly but surely back down to flat as though it is reading cold. Any ideas would be great thank you

 

[Luke4efc]

Sounds like the thermostat is stuck open. Are you noticing that the car takes ages to warm up?

[Focus2k6]

Hi, thanks for reply

It does take a while to feel  warm air coming In from fans inside the car and I did notice after driving for like 40mins that when I put the heaters on full  it was just warm air not hot

Also I can go for a 30 mile drive and the temp gauge won't budge (stays cold) except for very small movements if I am at lights for a bit. then if I pull up after a good drive for say 15 mins the tempreature goes to normal and stays like that if I don't move, but as soon as I drive off and at a steady speed it will slowly drop to cold(60°)

I had my engine running in a car park the other day and I got the car up to normal temp and I drove round the car park slowly (didn't go past 10mph) for about half an hour and the temp stayed bang on normal (88°) and then  as I was driving home it slowly dropped down except for the pauses at red lights 

It's effecting the efficency of the car aswell  it's running at 21MPG 

Cheers. 

Si. 

[Luke4efc]

Yes that definitely sounds like a stuck open (or at least partially stuck open) thermostat. Cheap and easy enough to replace.

[Focus2k6]

Excellent I will sort a new one out and post back results   thanks very much for your help

[CrazyInWeston]

On 1/5/2019 at 4:22 PM, Focus2k6 said:

It's effecting the efficency of the car aswell  it's running at 21MPG 

WTF? I've owned my 2005 1.6 Ti-VCT coming up to 18 months now, and my car has the exact same problem, engine never warms up, unless in stop/start where it'll reach optimum and stay there, just like yours.... But I've never had mine at 21MPG, That is bad, lowest I've had was 27mpg but I did have kinda the wrong oil in it at that time, my current Winter MPG EVEN WITH TWO TYRES that have a slow leak and being slowly deflated and I only inflate them weekly, 32MPG, my summer 34/35MPG.

Thing is right, I am astonished as you are, I rev the beans off my engine, dont change gear till 4000RPM at least, even in 1st - keeping it in 4th gear well past 30mph (because we all know we can put it in 5th here) AND the most surprising of all, hover around 90mph on the Motorway, my MPG just climbs even higher - I really do not understand it.

 

Edit: Another thing, my car uses up no oil whatsoever! Despite the high revs, speed etc, I last checked it last Monday, and the oil level was excatly the same as it was 14 months ago!!! (Havent so far been able to afford the annual service)

[Botus]

tractors with slow warm up may be a result of the EGR being tampered with

on vvti petrol's some car's had an electrically heated thermostat that works in conjunction with engine management (costs a fortune £110) when the heater element pops it runs hot and the fan runs almost continuously

others got a conventional one and they are £30 - its quite common for a stat to wear out on lots of cars