Since July, the Ferrari junior driver appeared in a Haas cockpit on seven Friday mornings at grands prix.
“I don’t think it helped us or our drivers,” Haas team boss Gunther Steiner told Ekstra Bladet newspaper.
“I cannot say how negative it was, but it was not positive. We will see what we are doing next year, but we have not talked about it yet,” he added.
Italian Giovinazzi has been left out of the Sauber race lineup for 2018, even though Ferrari’s other junior, Charles Leclerc, was accommodated.