Possible causes include: clogged battery connection, clogged clearomizer connection, clearomizer low or empty of e-liquid, low battery power, inhaling too deeply.
Good clean contact between your e-cig battery and clearomizer/tank is essential for the best heat, vapour and flavour, so regular cleaning is essential (every couple of weeks or so for example).
Rubbing alcohol/surgical spirit on a Q tip/cotton bud is ideal. Clean the outside of the connection/contact area (for eGo batteries) and the inside too ensuring that you hold the battery upside down so gravity can take away any excess fluid. Paper towel can be used to dry the area if necessary.
For stubborn grime a cocktail stick is ideal for the threaded grooves, taking care not to break it off inside the battery, but don’t use anything metal.
Atomizer is probably dry or doesn't have enough liquid. Try adding 2-3 drops of e-liquid directly inside the centre of the atomizer. Some atomizers when allowed to dry out will need a few minutes for the liquid to be absorbed again. Remember PG e-liquid will provide less vapour than VG.
The atomizer may have too much liquid inside it and cannot fully heat up. Place the open end of the atomizer (where the liquid goes in) on to a paper towel and blow through the battery connector end as hard as you can. This will force the excess liquid out of the atomizer.
Also make sure your battery is charged or swap it with another known good battery to eliminate causes.
Atomizer may have burnt out and you’ll need to replace it but it’s possible that the central contact points between the battery and atomizer isn’t touching.
Take something like a wooden cocktail stick or piece of credit card (don't use anything metal on the battery) and gently pry the centre contact up on both the atomizer/clearomizer and the battery. This is a fiddly job so take care not to force anything out of place. For 510 style atomizers/clearomizers with a protruding screw, unscrew it a little.
Of course, if there's a problem with the battery, for example it's nearing the end of its life, it may not be able to generate sufficient heat to power your e-cig. If you think you may have this problem, please refer to our e-cig battery problems page.
E-LIQUID / JUICE INFO
COILS / ATOMIZERS
E-CIG TANK PROBLEMS
E-CIG BATTERY HELP
SUB OHM BASICS