Losing Coolant + Constantly Misting up

[jamie_300 0]

Hi there,

 

My C has stated drinking coolant, and seems to be misting up constantly. I don't know if the two problems are related!

 

The Coolant light came on, on Sunday, I topped it up with 100% water just to get it home. I completely forgot about it until I went out last night, and It comes on again last night, And again this morning. Every time I have topped it up using 100% water as it's summer (allegedly!) I have noticed some rust coloured substance in the expansion tank, is this related or a problem?

 

Also since Sunday it seems to mist up on every pane of glass constantly, and I have to have the heater on full blast to prevent it from misting up and blocking my vision!

 

Very very annoyed with it!

 

Please help!

[KIPVW 0]

Maybe water pump or heater matrix.

 

ALWAYS add coolant too though, thats what it does COOL, adding just water is asking for trouble as it also conditions the block and pipes too.

[Portent 0]

Has the heater matrix been changed recently? If not then it could be that.

[fendervg 33]

Heater matrix - not good - a pain in the backside to do.

[steveo29 0]

everything points to the heater matrix

[boost monkey 0]

Maybe water pump or heater matrix.

 

ALWAYS add coolant too though, thats what it does COOL, adding just water is asking for trouble as it also conditions the block and pipes too.

 

Pure water will cool much better than 'coolant' or more correctly Ethylene glycol. The EG is really there for protecting the metal parts from rust, and also lowers the freezing point as the mixture is now a "solution", obviously with different properties than water alone.

 

So, the water is best for drawing heat away (thermal conduction) but the EG is there to protect from rust and also ice in the pipes!

 

+1 for the matrix. Why else would it mist up inside?

[jamie_300 0]

Thanks everyone, Roughly how much does it cost to get a new part/parts? Is there anything else I should do while I'm doing the Heater matrix?

 

Thanks again! :)

[dannyboy 0]

Pure water will cool much better than 'coolant' or more correctly Ethylene glycol. The EG is really there for protecting the metal parts from rust, and also lowers the freezing point as the mixture is now a "solution", obviously with different properties than water alone.

 

So, the water is best for drawing heat away (thermal conduction) but the EG is there to protect from rust and also ice in the pipes!

 

excatly.Dont really like the word 'coolant' for EG because it confuses people thinking their engine is going to melt if there no EG in with the water.

 

If it is the heater martix youd smell the coolant as it has a sweetish smell when you turn fan on.

Otherwise check the damp-proofing plastic on the back of the door cards,if they are torn or missing it leads to alot of damp and condenstion

[tony_ack 0]

Quick one on the heater matrix...

 

I've seen two types - one has round metal pipes looping over the bottom, the other is flat at the bottom. Are both type correct? As far as I can tell, all Corrados use the same matrix, and they also share the part with the MK2 Golf.

 

I only ask as I have a BNIB Valeo Golf MK2 matrix spare (flat at the bottom) and a Corrado that might benefit from it :-)

[KIPVW 0]

Pure water will cool much better than 'coolant' or more correctly Ethylene glycol. The EG is really there for protecting the metal parts from rust, and also lowers the freezing point as the mixture is now a "solution", obviously with different properties than water alone.

 

So, the water is best for drawing heat away (thermal conduction) but the EG is there to protect from rust and also ice in the pipes!

 

+1 for the matrix. Why else would it mist up inside?

 

It can also mist up if the foilage seal has gone and seeping water in there too!

 

Also if you like in a hard water area not adding coolant will cause the pipes and arteries of the block to fur up quite considerably.

 

But then it's your car so feel free to ignore me. Winter on it's way though so you'd be better adding it anyway ;)

[SamG40 0]

If it is the heater matrix then as mentioned its a proper PITA. Go to GSF for the matrix, same part as from VW as far as anyone can tell (same make) but its a lot lot cheaper.

 

Make sure you wash all the underlay out from under the carpets too as ours were soaked. The misses washed them in the bath to get all the coolant out and then dried them on the radiators.

[fendervg 33]

Apparently you can use Mk3 matrix as well, which is a better part. I wouldn't touch the GSF one, not worth the bother for all the labour involved if it fails, and I had two go wrong on my old Golf GTI.

[carrots 1]

i bought a cheap un off ebay lot of people say not to but mine seems fine

[eurospec 10]

Don't be scared of doing the matrix yourself. Everyone on here seems to think it's a pain in the ass, but i thought it was pretty easy to do! Don't even need the dash out, you can maneuver the heater out the passenger side of the dash.

[jamie_300 0]

Cheers guys, yeah the carpets were soaked, not too much of a problem as I want to put black carpets in there anyway! :)

 

I will be doing it myself, thanks for the tip Eurospec :)

[SamG40 0]

GSF supply Valeo ones just like the dealers do? Its the same thing!

[carrots 1]

i didnt take my dash out to do mine.bit tricky to get back in tho

[davidwort 0]

Just changed the heater unit on mine, bottom fixing into engine bay was siezed, what a pita that was, but it was the first time I'd done a matrix and like you say it's really not too bad to do.