Morning,

Looking for some help and i'm not sure if this is the right place. I was driving my Ford Fiesta Titanium X 1.6 Diesel on the motorway at 70mph when I noticed the engine temperature raising to the top. The engine overheating light came on so I dashed to the first lane and dropped to 60mph and nothing changed so dropped to 50mph and noticed the light go off and the temperature drop back to normal. The commute is 25 miles and I still have to get home and not sure what the problem is. 

Not sure if this is related, but about a month ago the heaters only used to work when above 60mph and if I dropped below that like when I got stuck in traffic the would blow cold and not heat back until the next day when I went above 60mph. They stopped working completely last week so it's been a cold trip and now this...

Any ideas would be great!

Stuart

 

Have you checked the coolant level?

low coolant level is often the cause of no heat out of the heater. my previous car was a fiesta 1.6tdci 2007.  The coolant level on that was down a long way when I found lack of heat from heater. Topping up curing the heater - but you need to find why level is low. On mine it was a leak where thermotstat cover bolts onto engine . location- if you are looking under the bonnet facing engine (looking towards the back of engine bay) it is on right hand end of engine near the top. probably black plastic.  on my 2007 mk6.5 it was very hard to see due to other stuff in the way, on the mk7 i think it is easier to see. Of course it could be something else - eg. water pump, radiator etc

Don't drive if there is an overheating problem. You will warp the cylinder head and blow the head gasket and it will cost a lot of money.

Years ago when engines and heads were cast iron, they would often survive overheating with no damage that needed fixing after resolving the coolant leak. Modern engines are much less forgiving and carrying on when overheating is very risky