Carlos Sainz was handed a drive-through penalty during the Mexico City Grand Prix on Sunday for speeding in the pit lane. This came as a second offense in the pit lane for the Spaniard, who has seemingly been struggling with pit limiter issues.
Sainz was initially handed a five-second penalty for speeding in the pit lane, as the driver committed the error during his first pit stop of the race. The 31-year-old came into the pits again on Lap 48 to serve the penalty but complained of issues with the car, with his Williams FW47 seemingly "jumping" in the pit lane.
This indicated pit limiter issues for Sainz, which was proven when the FIA reprimanded the driver yet again for the same infringement. The stewards then deemed that Sainz had sped in the pit lane again due to the issues he was nursing.
Since this was the second occasion this had happened, the stewards handed him a drive-through penalty, which Sainz served on Lap 58 of 71 in Mexico. This pushed him to the back of the field, as he lost out on numerous positions on track, including one to his teammate, Alex Albon.
The former Ferrari driver actually had a brilliant qualifying in Mexico, ending the session in P7 on Saturday. However, the penalty he carried over from the US GP meant that he had to drop down five places and start the race from P12.
Things only got worse for Carlos Sainz during the race on Sunday, especially due to the issues he faced with his Williams. On a track where the Grove-based outfit was expected to do well, they walked away without any points, with Sainz unable to finish the race and Albon finishing 12th.
Carlos Sainz struggles with pit limiter issues at the Mexican GP

As previously mentioned, Carlos Sainz came over the radio when he was in the pit lane and complained to the Williams team about a problem with the pit limiter. The driver said he was experiencing "massive jumping" inside the car.
In a moment that later brought him two penalties, Sainz came over the radio and said (via RacingNews365):
"The car is jumping in the pit lane! I don't know why, massive jumping in the pit lane. Like something is broken! Check the vibrations from the pit lane, on the pit limiter."
In the end, Sainz wasn't able to see the chequered flag after suffering a terminal issue on his FW47. The Williams driver had to park his car in the stadium section of the Autodromo Hermanos Rodríguez, causing a virtual safety car.
This VSC actually harmed Max Verstappen, who was in proximity to Charles Leclerc and could have made a move on the Monegasque for P2 on the final lap. In the end, Lando Norris won the race, with Leclerc in P2 and Verstappen third.