With other cars in years gone by....I remember there being a summer/winter setting on the air intake.

Recently with the cold weather, my Octy is running between 70 and 85 celsius, even after an hour or two driving...

I can't find a summer/winter setting instruction in the manual.

Does anyone know of one?

Never see this on a modern car for many years!

94 & 96 clio didnt need it, 2000 Mazda 626 didnt, 53 Mk1 octy didnt either.

Recently with the cold weather, my Octy is running between 70 and 85 celsius, even after an hour or two driving...

Failed thermostat :rubchin:

Hmmm, now there's a thought.

Although all has been fine up to now, the needle sits exactly at 90° with "normal" weather, but when it is now down at -10 to -25, it hovers from 70 to 85.

Perhaps it's just the weather.

AFAIK many VAG cars have a little software "fiddle" that tells the gauge to display 90 all the time, as long as it is somewhere near 90, so us customers don't think there is something wrong.

I would suspect a faulty thermostat, but just had a thought. If your Octy is a diesel and you are driving very gently at low revs it may simply not be generating enough heat to stay at normal operating temperature. The VAG diesels are very thermodynamically efficient (translation - they use all their fuel to move the car, none as waste heat which can be used to warm things up). If that is the case, try driving it with a bit more vigour, and tell us how that goes.

I have noticed on my Transporter when it is really cold that it warms up quicker going up a hill (and therefore working harder), then sometimes cools down when going downhill the other side. It can take 15 - 20 minutes to warm up to 90, longer if I am driving slowly and gently.

The thermostat is faulty if it doesn't reach 90 eventually.

My TDi takes almost 10 miles when driven very gently from cold at -7degC, but it does get to 90.

The thermostat is stuck open so the engine never heats up correctly.

Nothing to worry about, if the ambient temperature is very low and you are moving then the airflow throught he radiator will have a greater cooling effect. Basic physics.

The old, manual, flap was used to change the air intake to one taken from around the exhaust manifold from the normal one from the fornt of the car. It had ABSOLUTELY NOTHING to do with the engine coolant temperature, it wss about warming any air entering the carburettor ONLY. It became defunct with electronic fuel management and was never fitted to diesel cars. There are no vehicles manufactured with carburettors any longer and haven't been for many, many a year. No cars with fuel injection (so all petrol cars for about 10 years and all diesels ever) have a system that uses the air flow to induce the fuel, fuel being injected into the air flow, or to the combustion chamber. Air pre-warming is not any help in these situations.

Nothing to worry about, if the ambient temperature is very low and you are moving then the airflow throught he radiator will have a greater cooling effect. Basic physics.

Right, but if the thermostat has closed the external loop, this would not be a great factor...

You still have the incredibly cold air passing over the engine block, and this in itself also has a cooling effect especially at low temperatures even with the thermostat closed.

OK this morning the weather has warmed up to a relatively tropical -6, and all is back to normal, the gauge reads 90 again:)

It must just have been the chilling effect of being below -20 that wasn't allowing the engine to warm up properly. I might now consider fitting a cardboard sheet over half of the radiator to cut down the amount of arctic air flowing in.

I guess that when the outside temp was -25 and I'm doing 100 Km/h, the wind chill through the grill must be around -50 or so.

Many thanks to all for their replies.

tin foil over the front grills but not blocking off the air intake worked on a couple of my old cars.

As Fireftrm says, with the note that there was an interim period where the Winter/Summer air feed setting was effected by a thermostatic switch.

Last car I saw with a manual switch was the 1983 Chevette I learnt to drive in. :lol: My old 2000 Astra had an automatic switchover (worked off a vacuum feed and a wax thermostat) to draw air from the manifold heatshield or the cold air scoop.

pull the choke out futher that may help, or a blanket over the engine!!!

My old Panda had a wax thermostat and a spring loaded flap to divert air from around the manfold.

Trouble is, the little hose fell off and the carb froze going up a hilll one night which consequently lead to the car coughing to a stop at the side of the road

you could slip a piece of cardboard wrapped in tinfoil behind the grill and radiator. Tinfoil would be useful if you have forgotton some to cook up

Thats what the London cabbies do. Stick a large diamond shaped piece of card in the front grille.