Keeping the check engine light off.
Most vehicles sold in the past 20 or more years require that the fuel system be “sealed.” Otherwise, a sensor will illuminate the check engine light on the dashboard. One important step in keeping that light off is selecting the correct gas cap when you need a replacement. It is very important to choose the gas cap applicated for your specific vehicle. Some gas caps have the same type threads or attachment methods but the valving inside the cap is different. Automakers have different requirements, based on the fuel systems’ engineering, for internal tank pressures, both positive and negative. Too much vacuum or too much pressure build-up due to heat can cause problems. Too much vacuum can lead to a crushed tank. Too much pressure can cause a tank to rupture.
The fuel system in today’s vehicles typically vent through a carbon canister to reduce air pollution; this also saves fuel that might evaporate if openly vented. If the venting system becomes clogged or plugged, pressure can build in the tank. The gas cap is the last point of relief of this pressure. It has valving that will relieve high pressures before they become destructive. Getting the correct cap with the correct valving is critical.
Stant gas caps are built and applicated to ensure correct and proper fit. They have the correct valving for your vehicle. Stant has gas caps available for 98% of the cars and light trucks on the road today in the United States, according to R.L. Polk.
Installing the cap is also important in preventing the check engine light from coming on. Most original equipment fuel caps require being turned or “screwed in” until the cap clicks a few times. This is call “Torque over-ride.” It insures the cap has been sufficiently tightened to compress the seal that fits against the edge of the filler pipe. Most Stant caps should be turned until they click 3 times. If your gas cap does not have this feature, consider buying a different cap.
How a thermostat functions while driving:
The thermostat then opens as required in response to changes in coolant temperature to keep the engine's temperature within the desired operating range. Thermostats have a rated temperature such as 180°F or 195°F depending on make and model. It is essential that you choose the correct thermostat for your car.
Thermostat installation options:
Today’s thermostats nearly always have some type of housing they must either fit into or are already attached to the thermostat. In some cases, you can only see the housing and cannot see the thermostat.
The simplest thermostat housings are attached to the engine block and basically allow a hose—eithergoing to or coming from the radiator—toattach to the engine. This housing is unscrewed from the engine block. The thermostat will be resting on the engine block and can be easily removed and replaced. It is important the rubber seal or o-ring, if it has one, be replaced when you replace the thermostat. If a gasket was used instead of the seal to seal the housing to the engine block, it should be replaced. Be sure to clean the area where the old gasket had been in order to prevent leaks.
Someapplications do not use either a seal or a gasket but typically require the use of silicone “caulk” to provide a good seal.
An installation tip to remember is to put a clean rag in the hole where you removed the thermostat to prevent debris from getting into the engine.
Some thermostats can only be replaced by replacing the entire housing becausethe thermostat and housing are a single unit. These housings may be made of metal or a high temperature plastic. The housing is unscrewed from the engine block and replaced. Remember to clean the surfaces. The new housing usually has a seal attached to the housing.
Stant Corporation is the nation’s leading developer and manufacturer of automotive fuel systems, fuel caps, radiator caps and thermostats. Read more...
ABCs of Thermostats
- Purpose of a Thermostat
- Parts of a Thermostat
- How a Thermostat Works
- Thermostat Temperatures
- Why is a Superstat Super?
- OE & Alternate Temperatures