Lately, I have been very detached from Imam Mahdi atfs and my remembrance of him is void of any love or sadness of separation. It has been a major concern of mine for quite a few days because every time his name is mentioned, I don't feel that burning sensation that should be in the heart of a true shi'a. Is there anything that I can do to remember the Imam of our time more often and get closer to him?

Your concern for this feeling already shows the love of Imam Mahdi for you. It could be a test from Allah who wants you to keep on trying harder.
Some of the ways that scholars of Islam suggest are such as, reciting dua e Ahad every morning, giving sadqa for his well being, and infact, giving all your good actions as hadiya to Imam, and last but not least, being united with the Imam in all His actions eg praying on time the way he does, mourning for Imam Hussein a.s and so forth. Be careful in evaluating your actions day in day out and see what else is missing in your book of deeds.
If you are sincere in this which inshAllah you are, then it'll be in no time when you will begin to feel that burning sensation again and it will keep on growing i can promise you that!
Be sure to pray for all the Shia to get these great feelings too, that way, our imam will have enough companions to make his reapprearance happen soon inshAllah.