Time to warm the cabin - VW Polo diesel

[Smiley]

My wifes car - a 2006 Polo 1.4tdi seems to be taking a long time (even longer than it used to) to warm up the cabin these mornings - the engine temp has always taken a while and that has not changed - the car is running fine - the gauge sits dead on halfway at 90 degrees once it has warmed up.

My first thought was thermostat - but the car is running at correct temp once warmed up even in these conditions; then I thought of pollen filter - would that affect it? Then I read in the Haynes manual that there is an electric heater next to the heater matrix in the diesel cars - to take into account the longer warm up time of the diesel engine - anyone got any experience of these and how I would go about checking it?

or any other good ideas?

the other thing she mentioned is that the coolant hi-temp or low level warning light came on when she left the car idling on the drive to warm it up - of course she ignored it - drove off and it went out and did not come on again - until she left it idling on the drive again when it was stone cold- for a few minutes - then it went out again and has not come back on since. There is nothing wrong with the coolant level and the car is not overheating - coincidence or are these things connected?

Thanks

 

[wemorgan]

I believe the Polo has the same engine as my A2. So I'll ask the A2 forum and see what they say.

 

[mbenz76]

What about pollen filters?

When my air got weak and stopped being cold it was due to clogged filters. I imagine it could do the same to hot as well.

 

[Smiley]

What about pollen filters?

When my air got weak and stopped being cold it was due to clogged filters. I imagine it could do the same to hot as well.

Exactly my thought - see the second para of my original post. I will take a look at it tomorrow - easy enough to get at. it is 4 yrs old and has probably never been changed.

 

[x332race]

Air lock in system??

 

[yachtman]

My wifes car - a 2006 Polo 1.4tdi
Then I read in the Haynes manual that there is an electric heater next to the heater matrix in the diesel cars - to take into account the longer warm up time of the diesel engine - anyone got any experience of these and how I would go about checking it?

Thanks

We have a 2005 1.9tdi polo, the suplementary electric heater works when:-

air selector on screen defrost postion
fan speed on max
engine speed above threshold value
battery voltage above a threshold value

it draws near 40 amps so does help. easy to check as switching fan from max to down a step & back to max when other conditions are met, will make the voltage dip a little, observable on dipped headlamps at night, similar amount to putting on and off the heated rear window.

If you send me a vehicle code ie 9n polo etc and engine code eg aef and gearbox code I willlook up and send you details from ellsa win (a sort of vw equiliv to MB wis)

codes come from boot sticker,or copy usually stuck in service book

 

[Smiley]

Thanks Yachtman; you have ruled that out as the source of the problem as my wife never ever has the fan set to max - she hates it blowing much air at all - so something else is the cause.

Just been looking round the vw forum and it seems the heater control motors are not reliable but that would not cause a lengthy cabin warm up time - also saw a comment about broken water pump impellers reducing the flow of coolant and hence the flow through the heater matrix - that could explain the red overheating light on tickover as well. Is there any further damage that can be caused by broken water pump impellers in the cooling system?

Hmmm. Water pump is a PITA job on this car I think.

 

[lynall]

I doubt a water pump would cause overheating in a 4 pot diesel at idle, especially in this weather, easy to check take header tank cap off when engine warm/hot (be careful) and see if the coolant is moving, wont be a lot but should be some visible movement.

How long does engine take to get to temperature time or miles?



Lynall

 

[wemorgan]

I have to ask .....have you checked the fuses?

For the water pump, if you do change it, is it also worth changing the cambelt at the same time? I believe latest VAG guidelines are 5 year intervals. I had mine changed (including water pump) for £290 recently.

 

[bigyin1]

smiley - i had an A2 1.4 TDi and lived 25miles from work, i'd be at least 20minutes into my journey before the car warmed up sufficiently to give warm air, whereas the MB is <5minutes! As such i'd say this was normal for the VAG 1.4 TDi engine...

 

[x332race]

Volkswagen Repair: air lock in cabin heater, wv polo, rubber cone

 

[Smiley]

Thanks - we know it does take longer to warm up but having had the car for 2 years it now seems to be worse. Could an air lock happen without touching the coolant - it is still running the original fill.

re the overheating at idle - it does not seem to be overheating (I dont think anyway - will have a look later if I can find the car under the snow) but just the light that comes on - strange that it does this when at idle from stone cold - I was wondering if the engine block was getting hot at idle before the thermostat opened as a result of a faulty water pump.

The engine warm up seems to be normal; it is the warm up in the cabin that is taking longer - still cold after 10 miles.

 

[Smiley]

I have to ask .....have you checked the fuses?

For the water pump, if you do change it, is it also worth changing the cambelt at the same time? I believe latest VAG guidelines are 5 year intervals. I had mine changed (including water pump) for £290 recently.

Yes agreed - actually I had already decided to change the water pump at the same time as having the cam belt and tensioners changed - the car is 4 yrs old and has done 65k miles so starting to think about that. Did you use a new VAG water pump or a different one - with metal impellers? Was the £290 bill at a main dealer - does not sound too bad - I have looked at doing it myself but the access does not look good.

 

[wemorgan]

Yes agreed - actually I had already decided to change the water pump at the same time as having the cam belt and tensioners changed - the car is 4 yrs old and has done 65k miles so starting to think about that. Did you use a new VAG water pump or a different one - with metal impellers? Was the £290 bill at a main dealer - does not sound too bad - I have looked at doing it myself but the access does not look good.

That price was at a VAG specialist. I was told an OEM pump was used, so that would be the plastic impeller.

Stoke Audi have an offer on for £275 inc VAT (no water pump) The water pump is £30 extra (part only). Audi charge more labour for fitting. A bit cheeky I think, maybe this is negotiable.

ps. my cabin heater blows hot air after only 2-3 minutes. I think this is more typically judging by the A2 forum I read.

edit: with the cambelt change you'll also change the coolant. So you may kill many birds with one stone.

 

[x332race]

Thanks - we know it does take longer to warm up but having had the car for 2 years it now seems to be worse. Could an air lock happen without touching the coolant - it is still running the original fill.

re the overheating at idle - it does not seem to be overheating (I dont think anyway - will have a look later if I can find the car under the snow) but just the light that comes on - strange that it does this when at idle from stone cold - I was wondering if the engine block was getting hot at idle before the thermostat opened as a result of a faulty water pump.

The engine warm up seems to be normal; it is the warm up in the cabin that is taking longer - still cold after 10 miles.

I had a plastic impeller fail on a BMW....this was catastrophic causing the engine to overheat...howver, that was a big (2.8l) petrol engine.....may not have same effect on a diesel engine as they take much longer to heat up, especially in this colder weather and if the car is not driven very far, a failed pump could be the problem? My impeller just disintegrated....def was not a controlled failure...I get the impression that when they go, they go big time!

Doing a search on Polo coolant light brings up a number of topics saying that the sensor in the coolant tank can be dodgy, especially in cold weather?? This could be cause of light coming on??

 

[Smiley]

Thanks to you all for helping me with this; what a great forum this is - more help on another make of car!

 

[lynall]

After owning various landrovers all diesels for 10 years they all without exception put out heat in the winter after approx 4 miles so 10 miles tells me you need a new stat asap.
Even my old 50 year old series one used to put out heat after a few miles.


Lynall

 

[Smiley]

Thing is Lynall the engine temp gauge is behaving normally stays at 90 even in the very cold weather - it is just the heat in the cabin thats the problem. I double checked the coolant level today and it is spot on where it has always been so I think the diagnosis of a faulty sendor is the reason for the light coming on - but the heat in the cabin? I have read elsewhere that VWs are prone to the electric motors that control the heat flaps failing - and apparently they are a PITA to get to - the whole dash has to come out.....AAAGGGHHHH.

 

[kelvyn]

We had a water pump impeller fail on my wifes VW Passat tdi. She had been complaining about lack of cabin heat. I replaced the pump with one from GSF, it had a metal impeller as opposed to the plastic one that was replaced. I also took the oportunity to change the cambelt and idlers and while I was there the thermostat too. Fortunately access is good on a Passat as it has the engine north/south . You just take the front end off and its all there in front of you.
The heater now starts to blow warm after about a mile and on max is like a sauna.

 

[Smiley]

Thanks - were there any other symptoms of the water pump failure? where do the broken bits of impeller end up?

As I said in an earlier post I know that the water pump is a weakness on these cars and am planning to change it with the cam belt and tensioners sometime soonish - but not before it warms up a bit thats for sure. Your idea to change the thermostat whilst the system is drained down is a good one considering the small cost.