Question: borderlands 2 how to inject pod?
Answer: Travel to Tundra Express.
Lure Varkid larvae into transforming into adults. When Varkids enter their pods, run up and press X to inject the mutation. ... 
Kill the mutated Varkid.
Repeat this process 3 more times.
Pick up the Varkid corpse samples when they drop.
Return to Sir Hammerlock.