That's taken from TW's forum.
I have poor vapor production; what's up with that?
1. Make sure your battery has a charge. Swap them out and clean the connections. (I haven't had many problems with this, as I noticed the Tornado batteries hold a more thorough charge and dies off the last 2-3 draws before you get the OMG PUT ME ON THE CHARGER blinks.)
2. Make sure your tank has juice in it. Sometimes the wick will hold the flavor and be pretty close to dry without actually having a burnt taste, resulting in poor vapor production.
3. Check your atomizer to make sure it's actually working. ie: you hear the cracking noise that it's working, and it gets warm.
4. Try a different e-liquid. Sometimes tanks have problems with VG being too thick. Try a different mix with less VG and see if it wicks better. (I will also talk about this in part 2.)
5. Check to make sure your tank is properly inserted. If it's not pushed the whole way down, the juice wont wick properly effectively causing vapor issues.
6. Blow out the atomizer, prime it up and try again.
7. If all else fails, clean your atomizer. Running really hot water through it ought to work, boiling hot hot will work.Blow it out, put it on a paper towel and dry it. You can use a hair drier as well. If that's no good, try it again, but clean it with alcohol first ie vodka, everclear, or isopropyl alcohol (isopropyl alcohol isn't good to inhale, so make sure you run enough warm/hot water to rinse it out well).
Eww. What's that taste?
1. Again, check to see if the tank is empty. If it is, fill it, prime the atomizer, and puff a couple times. It'll go away.
2. Check to make sure the tank is properly inserted. As well as poor vapor production, it can burn your atomizer up if no liquid is getting there.
3. Check your e-liquid. Too much VG or Green Cow can be difficult to wick, but It is possible to make them wick better by thinning it out with PG (See below for other ways).
4. Make sure the atomizer is snug on the battery. I did an experiment to explain my findings after the rest of this I will tell what I have found.
Oh no! It's leaking everywhere!
1. Make sure the cap on the tank is not torn or deformed in any way. This can cause you to spring a leak. Also try a new Tank.
2. Clean the atomizer. The wick can become saturated and then the eliquid supersaturates it and it just rolls right off and into the cup filling up the metal mesh, which is like a sponge and will begin to leak after its full. Blow it out. Try to dry it with a paper towel and let it dry completely. If it doesn't work, try #7 in the first section.
-- There are many different ways of cleaning your atty. A search will yield many results. There is really no right or wrong IMO.