It is a common problem and it is not specific to mvp or to kanger; it is the design of the 510/eGo interface; center pin contact has too little tolerance; that's why some mods have floating pin or adjustable pin.
On the tank side if the tank has 510 thread one modification to help it is to file a milimeter off the 510 thread so that when you put the atomizer or whatever inside it, the center pin on the tank side visibly protrudes out:
Like in the pic below: this tank you see on the left side of the picture the center pin on the tank is visibly sticking out:
Even so though; that leaves the tendency to overtighten the tank and end up pressing in on the battery center pin too hard and causing other center pin issues on the battery side.
Look at this dripper: notice how the center pin on this one clearly protrudes; in fact it looks to me like it's adjustable becase the slothead is made for a screwdriver and there's no airflow involved here because it's a dripper with the airholds at the sides in the topcap.
On the tank side if the tank has 510 thread one modification to help it is to file a milimeter off the 510 thread so that when you put the atomizer or whatever inside it, the center pin on the tank side visibly protrudes out:
Like in the pic below: this tank you see on the left side of the picture the center pin on the tank is visibly sticking out:
Even so though; that leaves the tendency to overtighten the tank and end up pressing in on the battery center pin too hard and causing other center pin issues on the battery side.
Look at this dripper: notice how the center pin on this one clearly protrudes; in fact it looks to me like it's adjustable becase the slothead is made for a screwdriver and there's no airflow involved here because it's a dripper with the airholds at the sides in the topcap.
They are very small...