31 replies to this topic

[dirkthrust]

Hi all
Im new to this forum & to be honest im getting desperate to sort this problem :
I have a 2007 skoda octavia ambience & the heater is only working intermittently.
I have changed the heater matrix, the thermostat & today changed the control panel.
These are all things that I have been told that are the problem & nothing sorts it.
We are looking at the water pump tomorrow as another expert has told me that some
fins could be broken as the heater does seem to work better at high revs ??
Lastly I was told that there is some sort of a thermostat in the rear of the vehicle that
may control the temp, need help ???? .....

[skoda norm]

Looking at Elsawin, it says that there is a temperature sender in the footwell vent and in the middle vent, maybe these (or one) could be faulty. You need to remove the footwell vent to get at that one (unplug and turn 90 degrees to remove), and the dash panel has to be removed to get at the middle vent sensor. It doesn't mention how to test them, and I don't know if VAGCOM will tell you either? it may just be a case of elimination using a known good sender(s).
If your water pump wasn't working, I would have thought the engine would overheat?

Edit: The temp senders (above) may work with just a clean?, though I'm not sure having no experience of them. Also, just looked again - there are 4 senders - 1 in each footwell vent and 1 either side of the middle vents. I am guessing that the system has individual temp settings for the driver and passenger?

Edited by skoda norm, 09 November 2010 - 23:10.

[dirkthrust]

Hi There
Thanks for that & I will have a look at them tomorrow .
I'll keep you posted with the progress.

Again Many T's

[skoda norm]

OK cheers  

[skoda norm]

Some pics...

left footwell


right footwell



middle vents

[gallego1968]

Hi and welcome aboard.

[dirkthrust]

Hi All
Thanks for the help guys but still have not got the problem sorted ??
We thought that it had been a bad airlock as a big bubble of air came out of the expansion bottle.
We initially had the heater working red hot but found that if you were stopped at lights for a few mins
It started to get cooler & is now only working intermittently,
its a skoda octavia ambiente 1.9 td 2007, does anyone know where i might download a system diagram for the heating & cooling
on this vehicle ? Weird as it sounds the heater seems to work better at higher revs ??

cheers for the help in anticipation

[dirkthrust]

Hi Norm
It doesnt seem to have seperate controls, whatever the problem is it affects the whole heating system.
skoda octavia ambiente 1.9 tdi 2007

cheers for the help
dirk

[ap0gee1978]

Flap motors?  I reckon a proper fault code scan is needed, rather than replacing parts at random...

[dirkthrust]

hi mate
Checked flap motor in passenger side footwell & all aok,
no fault showing on scan.
think its some sort of circulation problem ??

thank you anyway.

dirk

[Tony_J]

I think I have the same problem on my 2002 Octavia Elegance TDI.  The heater gets fairly hot when I am at a constant speed at decent revs, on the motorway for example.  However when the car is stationary or stopping & starting the heater goes back to blowing otu cold air.  This happens with or without the A/C engaged.  
I doubt it's the mixer motor unless there's a chance it's opening and closing at random.  I would have thought it's the water circulation, maybe an airlock.  I'll have a search on how to bleed the system (unless someone can link me straight to it!)  

p.s.  Please don't reply "plug it into the diag machine."  I'm sure this leads straight to the problem in 99% of cases but  I don't have one and when I run out of DIY options I'll pay someone to have a look.  Right now I'm skintypoos so I'd prefer to keep what money I have!

[skoda norm]

Thermostat stuck open?

[dirkthrust]

Im still trying to sort the problem, starting to cost allot of money now, £450 spent so far.
All the obvious things changed, Water pump changed today £100.25.
Here's a list of all the stuff I have done to try fix this problem:
New thermostat changed twice.
heater matrix
heater control panel
Water pump.
System has been bled numerous times.
changed pollen filter
bypassed egr cooler
flap motor ok
had it on diagnostic machine, all read fine . no problems showing.
Same symptons as tony j has.
Here's a for instance.
Had water pump changed today as even though we checked it & was ok, so clutching at straws decided to change it.
It took about 10 miles to heat up, was aok for the next 25 miles then started to blow cold again.
Got to my destination. started my return journey & took a bit to heat up but stayed warm for another 20 miles or so then started to blow cold again.
There does not seem to be any reason for it to change temp,except that when the revs are a bit higher it seems ok ?
A crack in the head is been suggested now, but the engine is not overheating & no signs of a head crack.
If anyone has any other suggestions it would be appreciated.

Edited by dirkthrust, 03 December 2010 - 01:23.

[dirkthrust]

Hi Skoda Norm , thermostat changed twice, one point I will make is that the thermostat are only £3.50 each & at that price are they badly made & could possibly be that I've had 2 brand new faulty ones ??
Im definitely clutching at straws now :-/

Edited by dirkthrust, 03 December 2010 - 01:28.

[Tony_J]

Don't know what's going on but I have found that driving in town can be made warmer by keeping in a lower gear, so the revs stay up around 2k at least.  I'm sure it's doing nothing for fuel consumption but given the minus 8 degree temperature on my way to work this morning I can live with it.  
I thought it was a water pump issue because the heat only comes through at higher revs but seeing that replacing it has done nothing for others I'm not so sure.  Are there any filters in the system that could be clogged up?

[skoda norm]

dirkthrust, on 03 December 2010 - 01:26, said:

Hi Skoda Norm , thermostat changed twice, one point I will make is that the thermostat are only £3.50 each & at that price are they badly made & could possibly be that I've had 2 brand new faulty ones ??
Im definitely clutching at straws now :-/

I'm sorry Dirk, looking at what you've already done,  I'm out of ideas. You may have to seek a specialist  

[Estate Man]

dirkthrust, on 03 December 2010 - 01:07, said:

Im still trying to sort the problem, starting to cost allot of money now, £450 spent so far.
All the obvious things changed, Water pump changed today £100.25.
Here's a list of all the stuff I have done to try fix this problem:
New thermostat changed twice.
heater matrix
heater control panel
Water pump.
System has been bled numerous times.
changed pollen filter
bypassed egr cooler
flap motor ok
had it on diagnostic machine, all read fine . no problems showing.
Same symptons as tony j has.
Here's a for instance.
Had water pump changed today as even though we checked it & was ok, so clutching at straws decided to change it.
It took about 10 miles to heat up, was aok for the next 25 miles then started to blow cold again.
Got to my destination. started my return journey & took a bit to heat up but stayed warm for another 20 miles or so then started to blow cold again.
There does not seem to be any reason for it to change temp,except that when the revs are a bit higher it seems ok ?
A crack in the head is been suggested now, but the engine is not overheating & no signs of a head crack.
If anyone has any other suggestions it would be appreciated.

Are you sure a heater matrix hose isn't kinked? May sound odd but this is not unheard of and it's usually in a place that's hard to get at or see, often where it goes through the bulkhead.

[dirkthrust]

Hi Estate Man
The heater matrix hoses are accessible, both short with a bend  & we had a mess around with them yesterday, I even tried them the other way around ie: swopping the feed hose to the exit.
Didnt do anything, We also tried back filling the hoses & heater matrix to see if it excluded any air locks.
The one thing I can say is it seemed to change the way the heater was working, it seemed to get warmer faster than it had, but went cool after about 10 mins.
So im looking at the possibility that there is another airlock ? Im going to go through the process of trying to back fill them again & see if it does anything different.
If anyone has any info on bleeding the system that might help ? i would welcome any thoughts.

[dirkthrust]

Hi Tony
A couple of people said make sure that the pollen filter is clean, I took the one out completely to eliminate any chance that was causing the problem.
Thats the only one im aware of ?
My advice is dont spend any money just yet, Its starting to look like an airlock of some sort ??
how to sort it is the big issue.

cheers

[dirkthrust]

Hi All
finally got a solution to the problem, it turns out it was some kind of blockage somewhere in the system.
high pressure steam hose & blasted it through a few times , we now have a skoda with a working heater.
thanks to everybody for the hints & tips

dirk

[DGW]

Good to hear that it is fixed at long last!  I have moved this thread to the Octavia II forum where it is more likely to be seen by owners of that model.

[Tony_J]

dirkthrust, on 04 December 2010 - 23:48, said:

Hi Tony
A couple of people said make sure that the pollen filter is clean, I took the one out completely to eliminate any chance that was causing the problem.

Thanks for the tip, I'll have a look over the xmas break. Glad you finally found the solution to your cars problem, I suspect mine is suffering from same thing.
Cheers and Merry Christmas

[tobytyke]

Hi  Dirk,
                    i ave the same problem has you had hot then cold or sometimes not hot at all, done the therm, w/pump, temp senser, etc , tried flushing rad and matrix still the same , Can you give me more details on how you did yours (did you use a flushing agent) where did you conect the presure  hose  etc . regards  Dave

[mikeholroyd]

skoda norm, on 09 November 2010 - 23:05, said:

the dash panel has to be removed to get at the middle vent sensor.

No it doesn't. Removing the dash panel is a major job, and the sensors are perfectly accessible by simply lifting out the lidded box on the top of the dashboard. Just lift this out from the bottom, swing the box out of the way, without even disturbing the wiring to the hazard switch, and you'll see the sensors right there at the top, in the heater pipes, located above the radio. As already said, 90 degree turn, and they are out.

Two minute job to access and remove.

regards

Mike

Edited by mikeholroyd, 19 January 2011 - 05:52.

[dirkthrust]

mikeholroyd, on 19 January 2011 - 05:51, said:

No it doesn't. Removing the dash panel is a major job, and the sensors are perfectly accessible by simply lifting out the lidded box on the top of the dashboard. Just lift this out from the bottom, swing the box out of the way, without even disturbing the wiring to the hazard switch, and you'll see the sensors right there at the top, in the heater pipes, located above the radio. As already said, 90 degree turn, and they are out.

Two minute job to access and remove.

regards

Mike

[dirkthrust]

Hi Mike
Do you think the problem im having  might be something to do with the sensor ??
Im at the end of my tether to be honest.

Dirk

[mikeholroyd]

dirkthrust, on 29 January 2011 - 17:56, said:

Hi Mike
Do you think the problem im having might be something to do with the sensor ??
Im at the end of my tether to be honest.

Dirk

It's not going to hurt to clean the sensors. They are literally just strips of circuit board, and can be cleaned with electrical cleaner.

Mike

[dirkthrust]

mikeholroyd, on 30 January 2011 - 07:09, said:

It's not going to hurt to clean the sensors. They are literally just strips of circuit board, and can be cleaned with electrical cleaner.

Mike

[dirkthrust]

Hi Guys
Just an update as to where im up to, I took the car to skoda for a diagnostic & they came back with this info:
One of the pipes (from the exaust coolant pump to the back of the cylinder head) had a pinhole size hole in it,
& that it could do with further investigation at a cost of £900 to take the head off, which of course im not going to do.
I replaced the hose in question this morning & so far so good, heater seems fine & not losing water .
If the problem does arise again im sure  the head either has a crack in it or its warped.
i hope this info helps anyone with same problem.
Just a last note, the pinhole only became visible whilst it was under pressure & would have blown out steam
so there was no evidence of the leak as it was dispersing as it was blowing out of the hose.
if it has fixed it i cant believe i've spent all that money for nothing (
fingers crossed
dirk

[dirkthrust]

dirkthrust, on 03 February 2011 - 14:19, said:

Hi Guys
Just an update as to where im up to, I took the car to skoda for a diagnostic & they came back with this info:
One of the pipes (from the exaust coolant pump to the back of the cylinder head) had a pinhole size hole in it,
& that it could do with further investigation at a cost of £900 to take the head off, which of course im not going to do.
I replaced the hose in question this morning & so far so good, heater seems fine & not losing water .
If the problem does arise again im sure  the head either has a crack in it or its warped.
i hope this info helps anyone with same problem.
Just a last note, the pinhole only became visible whilst it was under pressure & would have blown out steam
so there was no evidence of the leak as it was dispersing as it was blowing out of the hose.
if it has fixed it i cant believe i've spent all that money for nothing (
fingers crossed
dirk