A sudden, unpleasant harshness in your vape, often described as a scratchy throat, a painful burning sensation, or an acrid, burnt taste, indicates an immediate malfunction in your device or a change in your e-liquid. This sensation, known as a “dry hit” or excessive “throat hit,” signals that the liquid is vaporizing improperly or that the vapor is too irritating to the respiratory tract. Since the experience was previously comfortable, the focus shifts to troubleshooting the specific component that failed or changed unexpectedly.
Coil and Wicking Failures
The most common source of a sudden harsh sensation is the failure of the heating element or the cotton material designed to supply it with liquid. A burnt coil occurs when the cotton wicking material inside the atomizer head becomes charred because it was not fully saturated with e-liquid before firing, or because the liquid supply ran dry. This charred cotton residue causes the distinctly acrid, metallic, and harsh flavor that often leads to coughing fits.
This degradation often appears sudden because it is cumulative. Sweeteners in the e-liquid caramelize onto the coil wire over time, forming a residue known as “coil gunk.” When this layer becomes thick, it acts as an insulator, causing hot spots on the wick that lead to immediate burning even with adequate liquid. The coil’s lifespan is finite, and this buildup signals that the coil needs replacement.
A dry hit results from the coil heating up without enough e-liquid on the wick. This occurs if the tank runs too low, if the cotton is tightly packed and cannot absorb liquid quickly enough, or if the device is fired rapidly without allowing sufficient time for the cotton to re-saturate between puffs (chain vaping). To prevent this, ensure the cotton is fully primed by dripping liquid onto the exposed wick material before installation, and allow the tank to sit for several minutes after filling.
Power Settings and Device Configuration
The power settings on your device directly influence the temperature and efficiency of vaporization, and an incorrect setting can immediately induce harshness. Setting the device wattage too high for the coil’s resistance rating is a frequent cause. When excessive power is delivered, the coil heats the e-liquid faster than the cotton wick can draw new liquid, resulting in a partial dry hit and an uncomfortably hot, sharp vapor.
Every manufacturer-made coil head has a recommended operating wattage range printed on the casing or packaging; staying within this range is necessary for optimal performance. Using a wattage above this maximum generates temperatures that quickly degrade both the e-liquid components and the cotton wick. Conversely, using a wattage that is too low means the liquid may not vaporize efficiently, causing the coil to gunk up prematurely.
Unexpected issues with the device’s electronics can also contribute to sudden harshness. If the device screen displays an unusual resistance reading (measured in Ohms) or if the power delivery seems unstable, it may indicate a poor connection between the coil and the device’s contact pin. This instability can lead to inconsistent power delivery, causing the coil to overheat sporadically. For devices with temperature control (TC) mode, failing to properly set the coil material type can cause the device to deliver excessive power, bypassing safety limits and leading to a severely burnt vapor.
E-Liquid Composition and Quality
Even with a perfectly functioning device, the chemical makeup of the e-liquid is a major factor in harshness. Propylene Glycol (PG) is a primary base ingredient known to carry flavor and contribute significantly to the “throat hit.” A sudden switch to an e-liquid with a higher PG-to-Vegetable Glycerin (VG) ratio (e.g., 70% PG/30% VG) will inherently produce a sharper, more irritating sensation than a high-VG liquid, which is smoother.
Nicotine concentration and type also heavily influence perceived harshness, which changes if you inadvertently pick up a higher strength. Freebase nicotine, the traditional form, has a higher pH level, making the vapor more alkaline and resulting in a stronger, sharper throat hit, especially above 6 mg/mL. Nicotine salts are chemically modified with an acid to lower the pH, allowing for much higher concentrations (e.g., 20 mg/mL or more) while delivering a smoother inhale.
The quality and age of the liquid can degrade and cause a sudden change in taste. E-liquid that is old, improperly stored, or exposed to light and heat can undergo oxidation, especially the nicotine component. This chemical change can make the liquid taste peppery or harsh. Certain flavorings, particularly citrus, cinnamon, or mint, also contribute to a naturally sharper throat hit, and a change to one of these profiles can feel suddenly harsher than a milder flavor.