Hi boys and girls,

I'm pretty sure this will be the wrong place to comment and there is already a topic out there but this is my first car forum visit ever so I do apologise.

My problem is I have a 07 focus with to me ( no mechanical knowledge ) a very strange problem, the issue is my car will get up to temp bang on in the middle of temp gauge it will then drop to 60c and the electric fan begins to run constantly. I have checked all fluid levels and checked for leaks etc and I yet to find any.

The car will then blow out cold air despite being on the hottest setting and no change of temp gauge after 30 minutes worth of driving. If I could please get some help or some advise from someone who has had this problem or knows about it then please don't hesitate to reply here or even email.

Thanks for your help

Harry

It could be the thermostat opening up and then staying open. Strange the fan is coming on though as this suggests a part of the engine where that sensor is, is getting too hot which sounds like an air lock.

Is there pressure in the system. Try squeezing the hoses when the engine is up to temperature. Check is both top and bottom hoses to the radiator are the same temperature. If no pressure try changing the expansion tank cap initially.

Same as above change the expansion cap first drive with heater on hot for a bit and see how that goes also do a dash check find the engine temp and see what it registers it may be a faulty temp sensor for the coolant

Thanks for the quick reply gents, just checked and there is pressure in the hose. Also had checked to find any faults by holding the reset button for miles etc when the ignition is off and then turning back on which has shown no faults. the only thing that has changed is the engine warning light has now disappeared. I thought it may be a faulty thermometer. Just trying to rule out a few issues before paying a lot of money at my local dealer.

I find it cheaper going to a dealer they usually find the fault most independants change 3 or more things before getting it right costing more in the long run.

The fault wont show up on the dash test it will need plugged in to a code reader a faulty sensor doesnt always throw up a code though

I think I will have to, I'm stumpt. On watching the engine temp from the led display it goes from between 90-100c then suddenly dropped to 13c then 0c which caused the fan to come on and put the engine warning light back on.