This question concerns a Ford Focus 1.8 Zetec E petrol engine. Do you know how much engine oil e.g. in litres or milliliters would have to be added the cause level sump to?

The exact amount of oil needed to bring a Ford Focus 1.8 Zetec E petrol engine's sump to the correct level will vary slightly depending on the specific model year and any potential oil leaks. However, a typical oil capacity for this engine is around 4.2 to 4.5 liters (or 4200 to 4500 milliliters).

Crucially, you should not just add oil to reach a certain level in the sump. You should use the dipstick. Check the dipstick to see the current level *before* adding any oil. Add oil in small increments (e.g., half a litre at a time), checking the dipstick after each addition until the oil level reaches the "full" mark between the minimum and maximum levels on the dipstick. Overfilling is as bad as underfilling, and can damage your engine.

Always refer to your owner's manual for the precise oil capacity and type recommended for your specific Ford Focus 1.8 Zetec E. The manual will provide the most accurate information.