Leaky Gas Cap?
The check engine light often leaves the driver wondering if the vehicle will be reliable enough to get either to a service garage or back home . Often the reason the light is on is to provide a simple warning to inspect a system for condition. In fact the most often reason this light illuminates is simply an improper seal of the fuel cap.
The gas cap is a simple but vital component that is found on virtually every car and truck on the road. The purpose is to provide a removable seal that prevents dirt, debris, and road dust for entering the gas line system. This cap also part of the the vehicle's evaporative emission control system.
As fuel vapour in the gas tank evaporates the "evap" system is designed and to hold captive and use these fumes in combustion. As this cap is frequently removed to permit fueling, the seal can wear out over time and will present a few symptoms that can alert the driver to the potential issue.
1) Check Engine Light comes on
An illuminated check engine light is often caused by a leaking gas cap. If the computerized control system detects a leak this light will be triggered to alert the driver to the condition. The Check Engine Light can also be set off by a wide variety of other reasons so having the vehicle computer scanned for all conditions is highly recommended as a potentially more serious problem may nipped in the early stages.
2) Smell of fuel from the Vehicle
Another symptom is a clear and distinct odour of fuel. A worn gas cap may cause fuel vapours to leak from the filler neck of the gas tank assembly. This of course will result in an easily detected fuel smell.
3) Cap does not tighten
The most common symptom of a miss fitting gas cap is that the cap will not tighten properly. The cap is designed to click as the exact amount of torque or tightness is applied to the rubber seal at the base of the cap. If the cap does not click or does not release easily it is often the result of improper fit as the gas cap is not working properly and needs to be replaced.
An improper seal on the gas tank is not necessarily going to cause some urgent or major performance issues. However, it will likely prevent a vehicle from passing an emission test or certifying that the vehicle is compliant the emission standards of the jurisdiction. The fuel smell alone is often the biggest concern.
A proper test by a qualified technician can identify the concern quickly and reasonably. As with most vehicle concerns, early correction can save a huge expense.