Good day, I've had my Fiat Siena for quite a
If the oil appears to be coming out between the block and cylinder head, the suspect problem is a head gasket that isn't sealing properly. If you changed this out already and it's still doing it, the block AND/OR head itself may need to be shaved to correct a slight warp or bow which is keeping the gasket from doing it's job right. A quality machine shop can correct the head/block, and a good mechanic will know how to check to see if the block and cylinder head planes are in tolerance.
If the oil appears to be escaping from between the head and valve cover, you can try removing the gasket there, cleaning the valve cover AND the head around the edges with a degreaser and again with some towelettes with alcohol (after its been degreased), then applying a thin coat of RTV sealant to each side of the gasket before installing it and equally tightening the screws down. These gaskets are a little more forgiving (thicker) than the head gasket because the casting of the valve covers are not as tight, but a bad seal is a bad seal. Just be sure that when using RTV to seal a gasket, both surfaces its going to come in contact with is absolutely free of oil deposits or dirt so it can grip and do it's job. Allow the gasket to cure/dry according the directions on the product and do not put it on and start the car up right away or it'll just spread oil again and the seal will generally fail quickly.
2003 Fiat Siena
on Nov 29, 2017