Hi there my car start show me a message " ENGINE OIL CHANGE" I changed the oil but still the message i went to the garage and the mechanic say it could be engine oil pressure sensor, we changed but the message still appear. Any idea what could be.

Its going to be the service interval in the ecu - they don't know when the oil is changed unless you go into the ecu and tell it and reset the service intervals. If its been serviced take it to a garage if you don't have the leads and software to access the ecu and ask them to reset the service intervals.

If its not been serviced recently then that is telling you its time to service it, or at the very least change the oil. Not sure what intervals that ecu will record but on my old alfa there was an interval for services and a separate one for oil - so perhaps its been serviced and reset but the separate oil one was missed..?

If you post further questions, please post in the Doblo section rather than here. Thank you.
http://fiatforum.com/doblo/

Awesome!