Weird heating on my car...

[S2central.net]

Sitting waiting in the car for one of the kids... Engine had been warm-ish, but the cabin was really cold. So I'm idling the engine and have the heat turned up full bapp - trying to encourage as much hot water into the matrix as possible - to heat me feet and demist the windeez...

The engine seemed to take ages to heat up - like 15 mins on idle and the needle barely moved... meanwhile all I have is cold air blowing out of the vents.

So I turned down the blower speed and set the heat control set to just in the hot side of halfway... WIthin a minute or so I start to feel hot air... Maybe coincidence or what ?

I've never checked my heating cables actually control the flaps the right way - but it seems a bit odd alright... Got me wondering if I have some sort of weird airlock in the system.

I notice on some days my coolant bottle level shows bang on the line, but other days its below the line by an inch - with a stone cold engine in both cases... Odd just odd.

There are no diagnostics on the coolant bottle so I dunno WTF is going on there....

[MikeLarwood]

Mine's similar - just takes ages to get flowing - sometimes until it hits normal running temperature.

[4WheelDrifter]

I always have the heat and fan turned off until the engine's warm. Otherwise you're just keeping the engine cool with the heater.
Does the Allroad slowly turn up the fan speed automatically as the coolant temperature rises? The A3/S3 climate does.

[mcandmar]

Same here, i leave it cold until the engine is warmed up. I'm obsessive when it comes to mechanical sympathy

You could try bleeding the system where it connects to the matrix, thats if the plastic bleed nipple is still intact. It is the highest point of the cooling system.

On the subject of heating, has anybody noticed when making a quick right hand turn the heater blasts ice cold air for a few seconds?

[Rocco]

+1 since i´ve bought my S2 car never give me very hot air like my last coupe 2.2e... the climate control on "HI" warm mode give only a small hot air and always never in 2 or 3 minutes ... it need a lot of time...

[S2central.net]

Mine has been bled OK...

The reason I turned the heater control down was to keep more water in the engine - I just never noticed this behaviour before.

[newsh]

Water doesn't go round the matrix till the thermostat opens IIRC. Anyway sitting at tickover doesn't put much heat into the water, a couple of runs through the gears at 1.5 Bar is much more effective, heat comes pumping out

[S2central.net]

Actually Mr newsh has a very valid point... the engine stat keeps the water away from the matrix until it opens. D'oh... It was a mighty cold day - I just expected to get more heat sitting at idle. I normally just jump in and drive and within 2-3 mins of driving its well up to operating temperature. Maybe I'm thinking about it too much, or maybe I wasn't sitting that long - the damn cold just made it feel like longer.

[goodall]

nope the thermostat is after the matrix nipple.
at least on a 10v anyway

that way you can get heat before engine fully warm

[goodall]

yup 3b/aby is same, pipe coming of from the water pump housing before the thermostat, and then i guess the return goes back the heat as par 10v

[4WheelDrifter]

Water doesn't go round the matrix till the thermostat opens IIRC.

I thought it was the other way round.

[newsh]

Doh, feels like it though

[denniselbows]

just change me thermostat at the weekend i don't think it makes a difference weather the thermostat is open or closed it still goes to the matrix. the thermostat opens up and lets coolant in from the rad and closes a hole in the block to stop the coolant round and round the block.

[Error404]

last time i bled my coolant i noticed the cabin was toasty before the stat had fully opened, as the rad hose to the stat was still cool
AfAIK the water pump will still circulate coolant around the engine (and heater) with the stat closed.

[S2central.net]

Ahh well I'm confused even more now...