Hi guys. I have a problem i think.
after not using my van for 1 or 2 months i went out in it yesterday and after 10mins (6miles) noticed my temp light was flashing rapidly

so i quickly turned round and went to the garage a few hundred yards away but, I found there was plenty of water in it but the oil was low so i bought a litre of oil and chucked it in.
this seemed to sort the problem and i drove a further 10 to 15 miles before reaching home all good.
However, went out in it this morning again and i only got round the corner when i noticed it was flashing again


As i have not had a problem with it until now and have not used it for a while i am a little gutted/confused and would like to know if anyone knows what the problem is that's causing this to happen?