Lewis Hamilton was quickest during second practice for the Malaysian Grand Prix despite limited running due to reliability issues.
Hamilton completed just four laps in the morning session before stopping on track, with Mercedes confirming an engine problem needed investigating. Having traced the cause to the power unit inlet system, the team admitted Hamilton could miss FP2 as it worked to fix the issue.
However, Mercedes quickly carried out the work and Hamilton was able to join the session around the halfway mark, going on to complete a further 16 laps and set a best time of 1:39.790 on medium tyres.
Kimi Raikkonen continued the encouraging start to Ferrari's weekend by beating Nico Rosberg to the second fastest time as he posted a 1:40.163. Rosberg was only 0.05s adrift of Raikkonen, but will be more concerned by the gap of over 0.4s to his team-mate.
Red Bull had a bittersweet session as Daniil Kvyat finished fourth fastest and little more than half a second off the pace set by Hamilton. However, while Kvyat's time hints at progress, team-mate Daniel Ricciardo was again hit by reliability issues as he completed just 8 laps in the session.
There were signs of Williams' pace as Valtteri Bottas was fifth fastest ahead of Felipe Massa in sixth, with both cars - as well as Sebastian Vettel on hard tyres in the second Ferrari - comfortably within a second of the fastest time.
Vettel's session was not without incident as he had a spin at Turn 11, losing the rear of the car on entry but stopping short of the gravel. The German was not the only driver to have such an incident, with Roberto Merhi causing a red flag a few minutes earlier. Merhi also spun off at Turn 11, beaching his Manor in the gravel and requiring the car to be recovered by the marshals.
While Merhi was limited to just six laps as a result of his off, Will Stevens managed a later run on medium tyres which saw him post a time nearly a second inside 107% of Hamilton, suggesting Manor should be able to qualify on Saturday.
McLaren again found itself at the back of the midfield having appeared slightly closer to the pace in the morning session, with Fernando Alonso and Jenson Button separated by 0.1s. Button himself was complaining of the car's handling in low speed corners and said on the radio that McLaren is "a long way from where we need to be".
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| Pos | Driver | Team | Time | Laps |
|---|---|---|---|---|
| 01 | L. Hamilton | Mercedes | 1:39.790 | 16 |
| 02 | K. Raikkonen | Ferrari | 1:40.163 | 29 |
| 03 | N. Rosberg | Mercedes | 1:40.218 | 26 |
| 04 | D. Kvyat | Red Bull | 1:40.346 | 17 |
| 05 | V. Bottas | Williams | 1:40.450 | 31 |
| 06 | F. Massa | Williams | 1:40.560 | 27 |
| 07 | S. Vettel | Ferrari | 1:40.652 | 29 |
| 08 | M. Verstappen | Toro Rosso | 1:41.220 | 30 |
| 09 | M. Ericsson | Sauber | 1:41.261 | 30 |
| 10 | D. Ricciardo | Red Bull | 1:41.799 | 8 |
| 11 | P. Maldonado | Lotus | 1:41.877 | 15 |
| 12 | F. Nasr | Sauber | 1:41.988 | 30 |
| 13 | S. Perez | Force India | 1:42.242 | 24 |
| 14 | C. Sainz | Toro Rosso | 1:42.291 | 31 |
| 15 | N. Hulkenberg | Force India | 1:42.330 | 28 |
| 16 | F. Alonso | McLaren | 1:42.506 | 25 |
| 17 | J. Button | McLaren | 1:42.637 | 24 |
| 18 | R. Grosjean | Lotus | 1:42.948 | 7 |
| 19 | W. Stevens | Manor | 1:45.704 | 12 |
| 20 | R. Merhi | Manor | 1:47.229 | 6 |
