It made its racing début late in the 1989 season - at the Portuguese Grand Prix - due to the team's wish to get any bugs out in testing beforehand which forced the team to use an updated version of their 1988 car dubbed the FW12C for the first 12 races of the season, by which time the FW12C had reached its development peak and both Patrese and Boutsen were eagerly awaiting the FW13.

The Belgian then won the final race of the year in Australia after a brilliant drive in very wet conditions, with Patrese third.

Walker reported that this was the reason the FW13 had so late in making its race debut as the team worked hard in testing to get the handling of the car right before putting it into competition.

The FW13B proved fast and reliable, with Patrese and Boutsen winning one race each – Patrese at "home" in San Marino (the San Marino Grand Prix was actually run at the Imola Circuit in Italy), and Boutsen in Hungary after also claiming pole position.

After French World Champion Alain Prost had announced he would be leaving McLaren at the end of 1989, he began talks with both Ferrari and Williams about driving for them in 1990.