As I've complained before, my car isn't reaching temperature. It's siting at about a quarter. All of the time.

I had the engine off but ignition on, and it sat correctly at half way. When the car was started it quickly dropped back down to a quarter.

Am I right to think the new thermostat will fix this?

Seems to me the cars temperature sensor is fine and able to detect the right temperature if the car, but a malfunction in the thermostat is letting too much coolant in and keeping it far too cool?!

I'm no expert, but that's what sort of sense I can apply to it. New thermostat should arrive tomorrow.

I also tried to bleed the system again and I think more air came out. (Hard to tell with the engine running). I think that there could be air getting in, but surely if this is true then coolant could also escape. The coolant is staying at the right level perfectly fine so I personally don't know what to think.

Any of your opinions are valued as always

Want the Panda to be back in tip top shape for our road trip to England on the 16th.

This is where it's sitting for anyone who wants to see it exactly

Thermostat stuck open is easy to check. Start the engine. Top hose right hand should stay cold.

I would check a new thermostat shuts properly by blowing down the outlet before fitting. At least one person with a Punta has got caught out with a faulty new part from eBay.

Does putting it in boiling water work? Saw some YouTube videos on that

When my thermostat was faulty, the temperature gauge never dropped to a quarter - it didn't go any more that down to the dirt notch

No need.

Yours should be stuck open. Or in my case the rubber sealing washer was missing.


Coolant should only circulate around the engine until it starts to get to temperature. As the thermostat opens hot coolant flows to the top of the radiator.


If its stuck open i.e. over cooling from start up the coolant will be flowing to the radiator via the top hose.

For the first few minuets there should be no flow towards the radiator. A bet you 5p that as soon you start the car the top hose starts to get warm.

Replacing a stat is completely straightforward, as long as you have a new gasket supplied and clean the remains of the old one off the mating faces.

You will lose some coolant so the question is do you drain it completely and give the system a flush, depending on when that was last done.

A new (working) stat will fix your problem. You could also blank off part of the grille to allow quicker warming-up over the winter - an old trick that no-one seems to bother with any more.

bluejohn125 said:

Replacing a stat is completely straightforward, as long as you have a new gasket supplied and clean the remains of the old one off the mating faces.

You will lose some coolant so the question is do you drain it completely and give the system a flush, depending on when that was last done.

A new (working) stat will fix your problem. You could also blank off part of the grille to allow quicker warming-up over the winter - an old trick that no-one seems to bother with any more.

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And a new hose clamp

When people say the cold icy weather affects the engine temp am I right to think that it doesn't make it go down by much at all?

The thermostat controls cold/cooler coolant flow. At low speeds (e.g. in summer) more will flow to the radiator. In colder conditions less will flow. Engine temperature should stays pretty much constant.

That's how I've managed to identify there's a problem.

If the thermostat doesn't solve it, what're my next steps?

Or is this almost certainly a thermostat issue

99,99%

gr J

The radiator provides a heat sink for the engine. The thermostat regulates coolant flow into the rad.

In the UK, there's not much point in blanking off the radiator. However, in very cold conditions we can get a situation were the coolant going back to the engine is too cold so the engine isn't at a fully even temperature.

Radiator blinds are used seriously sub zero conditions but normal UK winters are unlikely to get close to Alaska or Siberia.

DaveMcT said:

In the UK, there's not much point in blanking off the radiator.

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There's not much point blanking off the radiator on a modern car as no coolant will be flowing through it until the engine has warmed up (unless you are SB1500 and your thermostat has stopped working properly).

Blanking off the front grille is a different story as cold air flowing over the engine and exhaust manifold can significantly increase the warmup time. Ideally you'd want a variable geometry arrangement to control airflow through the engine compartment, as is already fitted to some higher end cars.

The benefits of grille blanking extend to higher ambient temperatures than you might think; I did some experiments with the Panda a few years back and managed to reduce the warmup time by 50%. This can significantly improve economy on a car used for short journeys as the Euro4 1.2 burns a lot more fuel when running in open loop mode.

IIRC one of the french car manufacturers sells an official grille blanking accessory; the instructions say that it can be left permanently installed whenever the ambient temperature is below 10C.

The thermostat is officially here!

In its glorious striped Ricambi Originali packaging .. complete with gasket.

Going to head and get a hose clip to fit it and then get it on tonight.

50 mile journey tomorrow, it's quite icy in N.I. as well so I'm looking forward to sitting in sauna like heat tomorrow.. I'll be bloody annoyed if not! lol

SB1500 said:

The thermostat is officially here!

In its glorious striped Ricambi Originali packaging .. complete with gasket.

Going to head and get a hose clip to fit it and then get it on tonight.

Click to expand...

Fingers crossed all goes well. Hopefully the f**k up fairy will be too busy doing her Black Friday shopping to put in her usual appearance.

The f**k up fairy got us good the other week... pouring half my two month old oil onto the bloody floor.. Made up for it by giving us a smooth process putting the flywheel oil seal in though! (must double check it tonight)

Thanks, I'll post back how we get on

I'm really surprised a car with no under tray warms up significantly faster with a radiator blanking plate. But here's the proof!! I will have to try it for my car as its often used for shorter journeys.

Block heaters are great for really cold conditions but not cheap and wont recover the costs in fuel savings alone.

SB1500 said:

The thermostat is officially here!

In its glorious striped Ricambi Originali packaging .. complete with gasket.

Going to head and get a hose clip to fit it and then get it on tonight.

50 mile journey tomorrow, it's quite icy in N.I. as well so I'm looking forward to sitting in sauna like heat tomorrow.. I'll be bloody annoyed if not! lol

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Don't forget to check its sealing shut before fitting. Not unknown for new parts to be faulty