The car was supposed to have the brand new, 900 bhp (671 kW; 912 PS) Ford TEC V6 turbo designed by Keith Duckworth and John Baldwin.

The THL1 made its debut at the Italian Grand Prix at Monza, with Jones qualifying 25th, 9.859 seconds behind pole sitter Ayrton Senna (Lotus-Renault), but retiring after just 6 laps due to an overheating engine.

The next race, the Belgian Grand Prix, had been rescheduled from 2 June so the team were not allowed to compete because they were not on the original entry list.

Jones then qualified 18th for the South African Grand Prix which saw the French Renault and Ligier teams boycott the race for political reasons, and the RAM and Zakspeed teams not enter, but withdrew before the race due to political pressure, however it was covered up as "illness" in order to not lose face, with the plan concocted by Bernie Ecclestone.

The car would still use the turbocharged Hart engine, but when the THL2 appeared in San Marino for Jones to drive, it was powered by the new, 900 bhp (671 kW; 912 PS) Ford TEC V6 turbo designed by Keith Duckworth and John Baldwin (Duckworth was one of the designers of the highly successful Cosworth DFV engine - the other being Mike Costin).