Valencia sacked manager Pako Ayestaran on Tuesday after four straight defeats to open the season.
Ayestaran was appointed in March to replace Gary Neville, but the poor start to the campaign sealed his fate after Sunday's 2-1 loss at Athletic Bilbao.
A club statement said: "Following a meeting of the board of directors, Valencia Football Club have taken the decision to release Pako Ayestaran from his role as first team coach. The decision has been made after analysing the current sporting situation and results.
"While the Club is finalising the appointment of a new coach, full responsibility and confidence is placed in Salvador Gonzalez -- "Voro" - to take charge of the first team during this interim period.
"Valencia Football Club would like to thank Pako Ayestaran and his coaching staff for their commitment, effort and professionalism during their time in charge of the team. The club wish him and his team the best of luck for the future."
Valencia CF Official Statment⬇️https://t.co/HI0dvEYOJI
- Valencia CF English (@valenciacf_en) September 20, 2016
The Spanish club are now in search of their ninth manager since the start of the 2012-13 season.
Former Valencia star Mario Alberto Kempes said earlier this week that he would be available to coach the club.
Under the 53-year-old Ayestaran, Valencia won three, drawn one and lost eight of his 12 matches in charge. This season, they have scored only five goals and conceded 10.
Valencia, bottom of the table with no points, take on newly promoted Alaves on Thursday at the Mestalla stadium before facing La Liga newcomers Leganes in Madrid three days later.