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Currently own a Vauxall Corsa (diesel), that is seemingly leaking engine coolant. Having bought over 3 bottles of coolant this week, and having to fill it up constantly, I will be taking it into a mechanic this weekend to see what's wrong. Because of this leak, the engine temperature warning light constantly lights up as the coolant runs out.
To save the expense of further bottles of coolant (and seeming that it's just leaking out anyway), and just as a temporary measure, can I simply use water instead? We are in the UK, so the temperature here currently is of no concern for anti-freeze.
Would this cause any damage in the short term? Depending on the fix, I might not be able to afford the repair straight away, would water cause an issue for a few weeks of driving? (Not major mileage, maybe 15 miles a day).