Hi there, I have a 05 Fiat Stilo Xbox 1.6 16v model.

Last year I remember topping up my engine coolant with Paraflu Up. I have recently read around that you are not meant to mix old Paraflu with new as it causes it to become a waxy substance that blocks up pipes.

Last winter my car was leaking a redish substance into the passanger footwell, believed to me to be engine coolant, leaking from the heating matrix. I bought some radweld as a temp fix really as it is meant to be able to seal pipes. It seemed to do the trick as I haven't since had any problems at all.

When I came to get my MOT last march, I was told there was next to no antifreeze in my engine coolant and so I got them to flush it out and replace with new. Therefore the leaking rad pipe may have been caused due to the pipes freezing up then expanding?? I'm not really sure??

Now it is coming around to winter and cold weather again I don't want the same problem to occur and there to be little antifreeze present in my engine coolant. My friend who knows a bit about cars said 'paraflu up' is the brand name for fiats antifreeze and that any antifreeze from halfords would be fine to top up with. However I have read about that you shouldn't mix different colours of antifreeze together as they contain different chemicals!

I am looking for advice on what antifreeze to top up with or if it doesn't matter really.
Thanks!

The red coolant is for alumunium heads, and the right choice for your car. Mix it 50/50 with water and you are safe. But you should cure the leak, not just remove the symptoms. Loss of coolant means overheating and engine failure.

I used blue coolant for a year when I was trying to find my leak, as blue is half the price. When I found the fault (radiator) I flushed the system several times with water, and put in red coolant. Don't worry about the brand. Paraflu doesn't exist in Norway anyway. The same is for Selenia.

Different types/colors should not be mixed.

The leak seems to be ok as I have had no leaks since using radweld last year. I'm more worried about having no antifreeze again as I don't want the pipes to freeze and expland. So was wondering what antifreeze I should use or if it doesn't matter as in the fiat booklet it recommends Paraflu up. The colour of the coolant in there at the moment is a red.

If the antifreeze was replaced correctly in March and there are no leaks, it won't need topping up.