Smoke coming from heater vents! '92 16v

[GrizzlyBear 11]

Driving to work today and noticed what looked like smoke/water vapour coming out of the heater vents above the stereo! I've pulled over and checked oil and coolant and all levels are fine. Smoke doesn't really smell, no electrical or burning smell at all, quite sweet actually.

 

I've researched and people say it could be the heated motor but mine is completely disconnected!

 

It only happens once the engine is on and I'm driving, and as I've said it's strange as my blower/heater isn't even connected as I'm waiting for a replacement!

 

Any help would really be appreciated!

 

Thanks in advance.

[Dox 23]

It sounds like the heater matrix is leaking, the sweet smell is the antifreeze

[GrizzlyBear 11]

I feared that was it :( big job too :(

[Dox 23]

I feared that was it :( big job too :(

 

Its a bit daunting when you start, but there's a few guides and how toos that makes the matrix repacement easier.

 

The best thing to do is to temporarily bypass the matrix to confirm the problem using plumbers copper fittings.

[GrizzlyBear 11]

Thanks Dox, just seems strange as my heater dosent work and has been disconnected for a while :( not sure whats triggered it to go.

[g0ldf1ng3r 15]

morning m8

 

i have a word document for matrix replacement via dash removal which has lots of pictures & shows nearly all screw/fastening locations etc

 

drop me a PM with your email addy if you want me to send it to you

 

also, try to make sure you get a Valeo branded matrix if you can - they are meant to be the better brand for such

[Jim 2]

Thanks Dox, just seems strange as my heater dosent work and has been disconnected for a while :( not sure whats triggered it to go.

 

How do you mean it's disconnected? Is the heater matrix itself completely bypassed in the engine bay?

[GrizzlyBear 11]

goldfinger - Thanks for that buddy, I'll pm you now.

 

Jim - sorry should have clarified, the heater blower motor that sits under the dash on the left hand side with the reisitor pack is disconnected as I'm waiting on a new one. Heater matrix is connected as normal and isn't bypassed.

[Dox 23]

Thanks Dox, just seems strange as my heater dosent work and has been disconnected for a while :( not sure whats triggered it to go.

 

Coolant systems typically run between 12 - 15 PSI (the pressure stops the coolant boiling by raising its boiling point), it seen many heat cycles in 20+ years and they're fragile any way.

 

It'll bee the plastic end caps that are leaking that surround the alloy core.

 

Bypassing it will prove the leaking core.

Edited July 25, 2016 by Dox

[Jim 2]

goldfinger - Thanks for that buddy, I'll pm you now.

 

Jim - sorry should have clarified, the heater blower motor that sits under the dash on the left hand side with the reisitor pack is disconnected as I'm waiting on a new one. Heater matrix is connected as normal and isn't bypassed.

 

Ah OK. Then yeah, it could still be the heater matrix that's gone. The heater matrix acts like a radiator in that it's always in-line and getting hot coolant through it so. All that happens when you set the heater to cold is that a flap is moved into place to block air from passing through it, and only allowing cool air directly through from the fan motor. Then when you want heat, the flap is opened and you get air passing through the matrix, which heats the air.

 

Best thing to double check is to remove the under shelf on the glove box and have a feel around the underside of the heater box (large black plastic in the centre at the rear of the dashboard) and see if you can feel coolant there.

[fendervg 33]

Blown or leaking heater matrix - don't have a passenger in the car when it's like that. It will end in tears.