Good day i have a 2001-2002 Opel Corsa Lite 1.4 can anybody please help me?

Good day i have a 2001-2002 Opel Corsa Lite 1.4 can anybody please help me? When I Start my vehicle (any time of day and when it cold or hot)it releases grey smoke from the exhaust and it smells of fuel and struggles to idle but if I push the accelerator for a few seconds the smoke stops and it starts to idle normal. It's using a lot of fuel but no water, have to top up the oil every now and then. I have replaced all of the sensors on the vehicle already and put in new valves and stem seals new rockers, new timing belt kit new plugs new coil pack changed filters but no change. I also experience that sometimes the engine stalls and struggles to start. I would really appreciate it if someone can assist me its starting to become expensive and I do love the car and would like not to have to sell it