Can you offer up what runs through your mind in making a decision for us?
For example... What things have you tried in figuring out your MBTI type? What thoughts ran through your mind when you were trying to determine whether you're a INTJ or INFJ?
I have taken numerous Online MBTI type tests. Given that the people which created the tests probably know more about type then I do I tend to trust the results I receive. These results have almost been a 50/50 split between INFJ and INTJ.
Logically I must be an INTJ as my hobbies (which I enjoy immensly) are all of a technical/scientific nature as is my job. Also, I tend to employ logic when making decisions.
Also, overall I have more of a T preference. For example I hate overly emmotional people, I'm not very emmotional and truth alwasys wins over tact.
That being said, I genuinely like people and tend to sympathize with most I meet. Also, I am very idealistic, and will often do things simply becuase it feels like the right thing to do.
I think you need to explore the differences between Ti and Te. An INFJ can be highly logical if his tertiary Ti is well developed. For example I've often explore issues myself in a strictly detached manner. Look at possibilities on both sides in order to make a sound, logical decision.
It is difficult to determine type by hobbies... especially for males. Society reinforces too many conventions.
Edit: There's no point in looking at BlueWing's INTJ Profile... he was after Ni... Te was a mere side thought in the description.