Engine Coolant?!

[TaylorHawkins]

I have had this problem now for about 6 months. At Christmas time I started the engine one morning and the coolant level light came on. Turned it off and on again like a PC :p and it was fine. A couple of days later it came on again half way to work, checked level and it was low. Bought a Litre bottle and topped up was fine. This has been Happened about 3-4 times now since Christmas? Its fine for a few months then all of a sudden its hit the minimum mark? Today I decided to try some radweld when I got home. Got in waited about 3 hours for the engine to cool down. The cars temp gauge said it was ok but it still felt a bit warm. The coolant level at this point was on minimum again, I opened the cap with a towel, there was a sound of steam and then the level shot up about 15mm above max?!?!?!?

I screwed the cap on and decided to blip it round the road and back. Got back and the level was back on max mark? Although when I went out it only took about 45 seconds for the car to reach its running temp?

I will wait till tomorrow morning now to check again but anyone have any ideas in to why my levels keep rising and dropping but never seems to be a leak under the car?!

Sorry if this makes no sense. But this has me stumped?! :no:

[LexVRS]

i have same problem, its like the level gets used up but when presuure is released its fine

[MoggyTech]

Replace coolant expansion tank.

[P20]

Moggy, would you care to expand on why? My partner has just bought a 1.2 Fabia and it had dropped its coolant, but restored when pressure released. Its just done it again this morning and put the warning light on. I haven't had a chance to look at it yet.

Sorry for slight hi-jack, found this doing a search.

[anewman]

What's the level like when stone cold? It sounds like it was still warm and pressurised to me.

[vRSsunroof]

Replace tank?

no vacuume?

Taylor - Did the cap hiss when you took it off warm?