Car blowing Cold air (Not hot air) - water/fluent run out possibly ?

Danny_G

If the car was blowing out hot air, with the car heater inside, but now only does cold air (even after 40 mins of driving, on max heat,,,, no cold air comes out) Car is Peugeot 406 ...

Then could this be that the liquid has finished ? and this image, is the image where the liquid goes in right ?

When opening this, unscrewing it and taking it off, should there be visible liquid at the TOP of this tank?

that can be visible at the top, when taking the lid off ?


if the liquid is not visible at the top, does that indicate it is run out? or this tank could still be half full ?.

and would that suggest, it needs to be topped up with coolant, and water ??

Ebe_Scrooge

Yes, that looks like the coolant filler cap. On most cars the expansion tank ( which is what the filler cap is screwed to ) is clear, and there should be a line on it to indicate the level. Normally the expansion tank should be about half full.

If you've completely run out of coolant then yes, your heater would not work - but neither would your engine.

Top up the coolant if necessary, using the correct mixture of water / antifreeze. Note that "antifreeze" isn't just used in winter, it also contains corrosion inhibitors so you need to keep the correct mixture, as per your handbook, all year round.

If the coolant level is correct and your heater is still not working, then it's something else. Common causes are a blocked heater matrix, or faulty diverter valves / flaps. Difficult to say without seeing it, but not too tricky to diagnose if you're prepared to have a dig around a bit. I'm still a fan of the old-fashioned Haynes manuals, but these days you can find out how to do most things on YouTube. Another useful site is http://www.peugeotforums.com/

Hope this helps.

Danny_G

Cheers.

How can it be 'tested' that the problem is that it is the fluid level which is low/ running out?

what can be done to test it? (even if it means tweaking things or getting under the engine...)


-and if taken to a mechanic, for a check...
what things would they do just to 'check' this ?

AdrianC

Just take a quick look.

If you've got coolant in the header tank - which you SHOULD be checking regularly anyway, along with the oil/tyres/lights - then that's not your cause.

If you've not got coolant in there, and you're still running the car, the heater is the least of your problems.

Is the heater not passing hot air at all, or is the fan just not working?
Does the heater control just go blue-red, or does it have numbers on it for the temperature?

Ebe_Scrooge

Just have a look at the expansion tank. If you can see it's about half full ( or ideally, if you can see it's right on the line marked, if there is one ), then you're fine. If not, mix up some water and coolant to the correct ratio in a jug, and pour it in until it's at the correct level. Replace the cap, run the engine for a couple of minutes to make sure it's all circulated, then check again.

Be very careful if you try to remove the cap from a hot engine - it'll be very hot water at high pressure. Cover the cap with a thick cloth and just give the cap a fraction of a turn to release the pressure first, before you try to remove it completely.

If the coolant level is low, and drops again a few days after you've topped it up, then this would usually indicate a leak ( unless the head gasket is on it's way out ). Leaks are often caused by a pinhole in the radiator, a perished hose, a loose hose clip. Park the car on level ground, put a sheet of clean paper underneath it and leave it for an hour or so. Any drips that appear on the paper will give you a clue as to where to start looking for the leak. It's not an exact science, but it gives you a good starting point. If no leaks are apparent, then try running the engine for a few minutes. Some very tiny leaks will only appear when the engine is running and the cooling system is pressurised.

Foxy-Stoat_3

What does the temperature gauge on the dash read? It should be in the middle after 10 minutes of driving.

Could be a number of issues here, main and first one is the coolant in the tank as others have said. The fluid isn't suppose to "run out", you may have a leak somewhere.

Take it to your regular garage, not Halfords!

Danny_G

Ebe_Scrooge wrote: »

Be very careful if you try to remove the cap from a hot engine - it'll be very hot water at high pressure. Cover the cap with a thick cloth and just give the cap a fraction of a turn to release the pressure first, before you try to remove it completely.

Does the cap 'have to' be removed when the engine is hot?

or can be removed in the morning, before the car has been driving (when it is cold) ?

does it matter, or yes?

Foxy-Stoat_3

Danny_G wrote: »

Does the cap 'have to' be removed when the engine is hot?

or can be removed in the morning, before the car has been driving (when it is cold) ?

does it matter, or yes?

NEVER remove when up to temperature as the water (over 100 degrees) will boil instantly when the pressure is released and you will have steam shooting out of the expansion tank!

Check the coolant when cold, there will be a min/max line on the tank.

I would read up on your owners manual for the car so you know what and how to check.

Strider590

Oh dear, oh very dear..... Doesn't sound like OP should really be in charge if a motor vehicle.

It sounds to me like the thermostat has had it. If stuck open this would stop the engine reaching operating temperature.

If the coolant was THAT low, then OP would be asking how to fix a blown head gasket.

Danny_G

Strider590 wrote: »

It sounds to me like the thermostat has had it.

Is this a long time winded job (by a mechanic)
How long should it take?


and also pricey ?

Strider590

I'd say £50 ish. The thermostat valve itself is £15 in eBay, the housing is another £15 (doesn't have to be replaced, but sometimes they prefer to).