AUTONET TV

What is a TPS? (Throttle Position Sensor)

You know you have an accelerator pedal; step on it and your vehicle is supposed to go.  But did you know there is a part in your vehicle that keeps track of where the throttle is? It's called the Throttle Position Sensor, or TPS.

The TPS is a sensor that helps your vehicle figure out the right mix of air and fuel is reaching your engine.  It does that by keeping track of the throttle and sending that information to your vehicle's computer.  Other factors play a role in how well your engine is performing, including air temperature, how fast the engine is turning over and air flow. 

When the TPS isn't working right, you may find your vehicle won't accelerate or doesn't have the power you're expecting when you press on the accelerator.  In some cases, it may accelerate on its own.  Sometimes your vehicle won't go over a certain speed.  Your Check Engine light may go on.

Any of these symptoms should be checked out soon.  If your TPS stops working right, your vehicle may not be safe to drive.  Fortunately, most vehicles have a "limp home" mode that will allow you to get off a busy road to a safe spot. 

Your service advisor can let you know which TPS is the correct replacement for your vehicle.  Your shop may have to re-program the new TPS so it works correctly with other software in your vehicle.

It's a fact of life these days that computers control many of a vehicle's functions. The sensors that feed information to those computers help make your vehicle work the way it was engineered to and keep you motoring down the road safely and efficiently.

McLearen Shell
3043 Centreville Road
Herndon, VA 20171
(703) 318-7744
http://www.mclearenshell.com

Mercury Rising (Hot Weather Vehicle Concerns)

The heat is on, and your vehicle takes a beating when it is.  Several of your vehicle's systems are under extra stress in hot weather, so here are a few to make sure are getting the care and maintenance they need.

It makes sense that the cooling system is one to make sure is in top shape.  Vehicle breakdowns in summer are often due to a problem with one of the cooling system's components.  Coolant levels have to be up to specs, the ratio of coolant to water must be correct and the hoses, pumps, belts and radiator must all be working properly in order to prevent vehicle overheating.

Summer is also hard on your air conditioning system.  You might find that no air is blowing out of the vents or maybe only hot air is coming out.  Air conditioning equipment is best diagnosed and repaired by a trained and experienced technician.  The problem could be in any number of components, including the condenser, compressor or blower motor.

You may think the battery gets a break in the summer, but heat will shorten the life of your battery more quickly than cold.  Your service facility can analyze the condition of your battery and tell you whether it's healthy or needs replacing.

Tires take a beating in heat, too.  Pavement can be scorching hot, and the sun's rays break down the rubber.  Watch inflation pressure in hot weather, too, since air expands the hotter it gets.  Your technician can check air pressure, tread depth, cupping and other uneven wear and diagnose the source of any problems. 

And don't forget brakes.  One video online says brakes on a car that were driven hard on a track reached temperatures as high as 500°C/932°F.  Heat can reduce stopping power.  A technician should periodically inspect pads, rotors, drums, lines and other components to find a problem before you lose the ability to stop.

Finally, engine oil is really put to the test when it gets hot.  Your vehicle service facility will make sure you have enough oil and the proper kind to keep your engine's components properly lubricated.  Help your vehicle beat the heat.

McLearen Shell
3043 Centreville Road
Herndon, VA 20171
(703) 318-7744
http://www.mclearenshell.com

Tire or Re-Tire? (Getting Tires Ready for Hot Weather)

Heat isn't easy on vehicle tires, and as the seasons change, make sure yours are ready to take the heat. 

Let's talk first about inflation.  Heat causes air to expand, so heat alone can raise the pressure in your tires.  If you are driving on overinflated tires, they won't have as much contact with the road surface.  In that case, it will take you a longer distance to stop.

On the other hand, you don't want your tires to be underinflated during hot weather, either.  That can cause your sidewalls to flex.  Friction will then hike up the temperature and your tire can be in danger of blowing from the added heat.

Other things can cause problems, such as uneven wearing.  Your service advisor knows the signs to look for and can diagnose where the wear is and what is likely causing it.  Another thing a technician will look for on tires is tread depth and the condition of the sidewalls.  Any cuts, cracks or bulges could be indications that your tire is not healthy. 

Oh, and one other thing.  Your tires could have plenty of tread left on them but still be dangerous.  And that is because rubber ages, gets brittle and cracks after time.  (Ever run across an old rubber band in a drawer that has never been used but breaks the second you try to stretch it? 'Nuff said.) Some tire manufacturers recommend replacing tires after 6 years of their manufacturing date.  Your service advisor can read a manufacturing code and tell you how old your tires are. 

Tire manufacturer Michelin used to have an ad slogan that said, "Because so much is riding on your tires." That includes you and your passengers.  Always keep healthy tires on your vehicle and make sure they're ready for whatever season it is.

McLearen Shell
3043 Centreville Road
Herndon, VA 20171
(703) 318-7744
http://www.mclearenshell.com

Losing Your Cool (Why is My Air Conditioning System Not Working?)

When you turn on the air conditioning in your vehicle, you expect cool air to come out of the vents.  You depend on it, especially in hot weather, but it can also be important in humid weather when you need it to help defrost your windows and windshield.

The air conditioning system has a lot of parts to it.  It has fans and blowers to move the air through the vents into the cabin.  It has parts that take hot air and cool it off. An electrical problem can be as simple as a broken switch or a broken blower motor. The air may not be getting cool because a hose in the system is broken or the refrigerant has leaked out. 

Two major components are the compressor and the condenser.  The compressor pressurizes the refrigerant, one step in the air conditioning process.  The condenser takes that hot refrigerant and cools it down. It also reduces the pressure.

Because the climate control system in your vehicle is so complex, it’s best to leave the diagnosis to a trained, experienced technician.  You can help the technician zero in on the problem by noting what is happening and being able to show them where you notice the issues. Note what’s going on and write it down. 

When you bring your vehicle in to us to look at, a technician will inspect the system, conduct tests to make sure there’s enough refrigerant, and check to make sure there are no leaks anywhere.

Air conditioning is now included in most vehicles.  We all have grown used to being able to keep the cabin comfortable no matter what it’s like outside.  Let us make sure your system is working the way it was designed to.  That’s definitely the cool thing to do.

McLearen Shell
3043 Centreville Road
Herndon, VA 20171
(703) 318-7744
http://www.mclearenshell.com

Keeping Your Cool (Coolant System)

No matter what the weather is like outside, your internal combustion engine expects to keep its cool all the time, even when it's really cold.  That's because engines create the power that moves you to your destination by a series of tiny explosions of a fuel and air mixture. In turn, that generates a lot of heat in a small space.

Your vehicle has a complete cooling system with a lot of different parts that work together to keep the temperature at a point where the metal engine parts won't heat up enough to warp.  Its lifeblood is coolant, a liquid that circulates through the engine (and, in most vehicles, the transmission, too) through a series of hoses and tubes. 

In order to get rid of the coolant's heat, your vehicle has a part you probably recognize: the radiator.  It does what its name proclaims: radiates heat.  The radiator has a series of thin metal fins that coolant goes through, and when outside air passes over them, the heat is dissipated from the radiator into the air.

The water pump (which is technically a coolant pump) is what propels the coolant where it needs to go. 

When there's a problem in the coolant system, it may because it's leaking somewhere.  A few things to look out for are the temperature gauge heading into the hot, or red, zone, fluid leaks under your vehicle, or the sweet smell of coolant under your vehicle after it's been parked.

If your vehicle has any of those signs, bring it in so we can check things out.  A technician will inspect the water pump and hoses for any signs of leaks.  They'll also look for leaks or holes in the radiator core or cores. 

One other potential trouble spot is the radiator cap that can sometimes fail to keep the required pressure in the radiator.  Once the problems are fixed, they'll add the correct coolant and you'll be on your way.  We want you to always keep your cool. 

McLearen Shell
3043 Centreville Road
Herndon, VA 20171
(703) 318-7744
http://www.mclearenshell.com