it's a little under 3 litres. so if you buy those 1 lit per bottle, 3 of those should be enough, or if you buy those 1 pet 4 lit ones, can keep as extra. many workshop buat bodoh straight keep the extras for themselves.
For those who are interested, found this interesting item on how the flashes given by the check engine light for Mitsubishi cars can indicate the specific problem encountered.