Opel COMBO Owner's Manual page 175

Capacities
Engine oil
Engine
including Filter [l]
between MIN and MAX [l]
Fuel tank
Petrol/diesel, nominal capacity [l]
Natural gas CNG, nominal capacity [kg]
Petrol, nominal capacity [l]
Short wheelbase version.
8)
Long wheelbase version.
9)
1.4i 1.4Turbo 1.4CNG
2.7 2.9 2.9
1.0 1.0 1.0
Technical data
1.3CDTI 1.6CDTI
3.2 4.9
1.0 1.0
60
16.15 kg 8) / 22.1 kg 9)
22
173
2.0CDTI
4.9
1.0