I have the same problem on my Audi, but only when it's really cold and slightly low on coolant. I'm 99% certain for me the problem is air, my Audi has a petrol heater and some additional heating hoses that are routed at about the same level as the coolant reservoir. I think when coolant drops below max those 2 hoses or one of them is causing trouble. Weird thing is it only happens when it's really cold and I'll be freezing my ass off halfway to town before I get heat from the vents.
The Mk4/5 Fiestas suffer badly with the heater control valves, when they do fail it causes issues with the engine temperature and also the heater inside the car. Not sure if it would be a similar story with the Focus'.
@@mike_themechanic I had a look on eBay and it was called a heater valve or coolant control valve, the pictures might help to identify if the car has one. I don't suggest that it will be problem, but seems a relatively cheap part to try before head gasket or water pump.
@@mike_themechanic I have absolutely no real mechanical skills as such only I’ve just replaced one doing similar things on my streetka but I’m certainly no mechanic anyway it was just a thought ..good luck with it 👍
cabin temperature sensor, right side under the steering wheel there is a round vent, pop the trim off and see if the senor is full of dust (there is a fan in it collecting dust) see if you have a fault code for it as well. Also if the cabin temp reached the set temperature it won't necessarily blow hot air, but in -30 it is unlikely. After replacing the thermostat does you coolant temperature still movind down after reaching 90c*?
That's what my local ford dealer said anyway. I was under the impression that there was another sensor at the rear of the engine, but they confirmed no . Let us know if you resolve this issue with the new pump...
My temp gauge doesnt move at all usually. when it does decide to move, it reads normal,( just below half way ). The car heater warms up in a timely manner and appears normal other than the guage. very strange. Im wondering if themostat is playing up somehow, of maybe sensor ?? anyone got any ideas ?? thanks 👍
If you are getting heat in to the cabin I would say the sensor is at fault if not then possibly the thermostat is at fault. When I changed my thermostat housing it came with a new sensor so it might be worth changing both.
@@mike_themechanic the only other place in a coolant system where pressure is low and air could be drawn into the coolant is at the water pump shaft. Or at least i cannot think of anything else 🤔
I changed the water pump when I changed the cambelt. I have wondered if that could be not working in some way and not pushing the water around the system as it should
Now that I've watched all the way through. Why not plug it in and have the engine heater on and bleed it. (Maybe both at the same time as it may push air into the main system?) Should have brought a petrol.
@robertjohnson8489 the electricity engine heater has no pump its just a block heater that heats the oil. The diesel heater has its own pump and I've had that started a few times and I do get heat when that starts. I'm starting to wonder if it's the water pump that's not pumping properly
