Hi all.

I’ve been experiencing a few issues with my car and I was looking for some advice.  I’ve had trouble demisting my front windscreen for a while now and can’t figure out why.  It was only on a drive home today where the temperature light came on my dashboard is when I realised there was a problem.  As I was moving off at low speeds there was a rattling noise coming from my engine. Then my car said low engine oil pressure which is weird because apparently I have enough oil.

I believe I’m not able to demist my windscreen because of how unbelievably hot my engine is getting when I drive the car.  I’m not sure why it’s doing it nor how to fix it.  I also checked but all my coolant has been used even though I filled it the other week.  I just assumed that it was because my engine was so hot.  I would really appreciate some advice and if someone could tell me if my assumptions make any sense.

Thanks.

Firstly, heat is what you need to demist a windscreen, so an extra hot engine wouldn't prevent that.

Usually, a damp screen means there is water inside the car.  If you can't feel it in the seats then it's probably in the carpets.  And as all your coolant has disappeared, that points to a leaking heater matrix.  I'll bet the carpet in your front footwells is wet.

Missing coolant is the reason that the engine overheated.  And the fact that it was left like that for so long means the engine has probably warped or cracked, which is why the oil pressure dropped and the engine was rattling.  (Oil pressure is not directly linked to oil level).

Overall, this is likely to be a major repair with high repair costs.  

54 minutes ago, TomsFocus said:

Firstly, heat is what you need to demist a windscreen, so an extra hot engine wouldn't prevent that.

Usually, a damp screen means there is water inside the car.  If you can't feel it in the seats then it's probably in the carpets.  And as all your coolant has disappeared, that points to a leaking heater matrix.  I'll bet the carpet in your front footwells is wet.

Missing coolant is the reason that the engine overheated.  And the fact that it was left like that for so long means the engine has probably warped or cracked, which is why the oil pressure dropped and the engine was rattling.  (Oil pressure is not directly linked to oil level).

Overall, this is likely to be a major repair with high repair costs.  

How will I know if my engine is warped or cracked?

1 minute ago, benpaterson said:

How will I know if my engine is warped or cracked?

Visually check around the engine for any oil or coolant leaks, especially where the block meets the head.

Have a pressure test done on the cooling system.  (But that will be pointless right now if the heater matrix is leaking - it won't hold pressure anyway)

Have a CO2 'sniff' test done on the cooling system.  This checks whether exhaust gasses are getting into the coolant through a crack or past the head gasket.

Have a cylinder compression test done.  This checks whether the cylinders can hold good pressure - if not, they may be cracked or the head maybe warped, or the head gasket may have failed.

11 hours ago, benpaterson said:

Then my car said low engine oil pressure which is weird because apparently I have enough oil.

Oh dear 🙁