AUTONET TV

No Yolk! Rotten Egg Smell (Sulfur Smell Causes)

The pungent smell of rotten eggs can send people running for the hills.  So when that odor is inside your vehicle, yikes!  Yolks!  The good news is that a trained service technician can search the source of that smell and stanch the stench… that comes from another words that begins with S.  Sulfur.

Fuel contains small amounts of hydrogen sulfide, but they're enough to stink up a vehicle when it's not properly burned.  You may know that the smell of rotten eggs can often be a sign of a catalytic converter that isn't working the way it should.  That could be due to age, damage or an abundance of oil that's clogging it up. 

If a sensor in charge of managing the fuel has failed, the engine can run with too rich of a fuel mixture.  That can overload the catalytic converter and allow some of the byproducts to escape without interruption from the chemical reaction that is supposed to prevent them from going out the tailpipe.

There's another possibility, but it's usually only in stick shift vehicles.  That's leaking, old transmission fluid.

Catalytic converter repairs are best left to a professional. Technicians at your vehicle service facility have equipment and training that can help them pinpoint the cause of this funky fragrance.  Once the cause is found, repairs made and/or parts replaced, the smell should go away fairly rapidly.

Dennis Road Automotive
11155 Dennis Road
Dallas, TX 75229
9722411901

The Truth about Tire Pressure (Tire Inflation)

Most light vehicles (under 10,000 pounds/4,500 kg) in North America sold from 2008 model year on have a feature that many people are confused about.  It's the tire pressure monitoring system (TPMS).  You may have some experience with it yourself if you own a newer vehicle.  Vehicles with TPMS have sensors in each tire that are supposed to warn the driver when tire pressure gets dangerously low.  That's important because tires that are significantly under-inflated can cause very serious accidents.

Unfortunately, many drivers think the TPMS does all the work keeping track of tire pressure. To them, as long as the warning light or gauge isn’t giving a warning, the tires must have the proper amount of air pressure in them.  That's not the case.

Tire pressure monitoring systems aren't all created equal.   Some give you a digital readout of the pressures in each individual tire.  But many simply have a warning light that looks like the cross section of a tire with an exclamation point in the middle.  If you don't know what it is, it's because it's not instantly recognizable as a tire.  In fact, one company that makes TPMS, Schrader Performance Sensors, surveyed drivers.  Their study showed that more than 40 percent of drivers didn't know that that warning light was. 

One out of 5 of the drivers who did know what the light was only looked at their tires after the light came on to see if they could see any that needed air; they never checked them with a tire gauge or had someone else do it.  Ten percent of them didn't do anything when the light came on.

In most vehicles with TPMS, the warning comes on only when the tires are more than 25% underinflated.  The American Automobile Association says that's under the pressure you need for safe vehicle operation.

The bottom line is once a month you should make sure your tires are inflated to the manufacturer's recommendations.  That means each tire should be measured with an accurate, external tire gauge.  To be confident you are getting a correct reading, take your vehicle to a reputable service facility where their equipment is calibrated and they know what they're doing.

Severely underinflated tires can contribute to an accident that kills or severely injures people.  The idea behind TPMS is well intended, but the system was never meant to replace regular inflation measurements and maintenance.  Periodically have your tires checked for proper inflation.

Dennis Road Automotive
11155 Dennis Road
Dallas, TX 75229
9722411901

Don't Start with That (Bad Starter Motor)

We've all heard that expression, "That's a non starter." When it comes to your vehicle, that's not music to a driver's ears. That sickening sound when you start the ignition and instead of hearing the engine crank, you hear it slowly turn over and your dash lights go dim. 

There can be many reasons a vehicle won't start, so here's a little history of how the starter came to be an important component of modern vehicles.

You have to move the engine's components to start it. The first cars had a crank that the driver would insert into the front, then start turning things over by hand.  When the engine started, you had to release that crank immediately or risk a broken arm.  Yes, it happened many times.  So, they came up with a better idea: an electric starter, which was a big advance in automotive technology.

With this system, an electric motor rotated a series of gears that turned the gasoline engine's crankshaft so its pistons and parts moved and the engine drew in air.  While this happened, electricity went to the spark plugs and fuel headed to the cylinders.  When the gasoline engine caught, the starter quickly disengaged. Hey, no more broken arms!

Modern systems use the same principle, so when your vehicle won't start, here are a few things to look out for that might point to the starter. 

If the engine turns over s-l-o-w-l-y, it may mean the electric starter motor may just be wearing out and doesn't have enough cranking power.  Bushings, brushes, wire windings and a special switch called a commutator may be going bad.

If when you engage the ignition you hear a faint click, that could be a symptom one or more of the starter's components have failed. If you hear a loud click, it could mean that an electrical switch called a solenoid may not be switching the motor on.

If you hear your engine start to turn over but then it stops and is followed by a grinding sound, some gears may not be meshing the way they should.

There may be many more causes (bad alternator, relay, battery, engine, key fob), so this is when it's time to turn it over to your service facility.  Sometimes they can send out their own tow truck or recommend a reputable towing company.

But it's best not to let it get to this point.  Starter problems often give you advance warning that there is a problem with "almost" not starting or "almost" not turning over.  So when you see that very first sign, "start" on over to talk this one over with your service advisor.  The opposite of a "non-starter" is a starter, and that is music to anyone's ears.

Dennis Road Automotive
11155 Dennis Road
Dallas, TX 75229
9722411901

Not So Cool (Air Conditioning Systems)

There's nothing quite like getting in your vehicle on a hot day, switching on the air conditioning and having warm air blow out of the vents.  You may have had no problem for months and then, one day, you are driving around in a sauna. You're hot stuff, but not in a good way!

So what goes wrong when the AC isn't working? It could be a lot of things because the system has many different components.  One thing that's a common cause is the vehicle is low on refrigerant (it used to be called Freon).  If that's the case, it's not as simple as simply adding more.  Sure, it may fix it quickly for a short time, but it's more likely than not that the refrigerant will just leak out again.

The original Freon used in air conditioners was destroying the Earth's ozone layer, so that's not used much any more.  But the one that's currently used also contributes to global warming, so it's important that as little of that escapes as possible.  So a technician will determine if there's a leak in your system, where it is and fix that before adding new refrigerant. 

Your vehicle also has an evaporator or two, and those can fail.  Leaks are often the problem with them as well.  The big component that can go bad is the compressor, often a victim of age, wear or neglect. 

A technician will also check to see that the blower is working correctly.  That's what blows that cool air into the cabin.  Sometimes the motor will fail, a relay will go bad or a fuse will blow.  As you can see, there are lots of different parts involved here! 

The good news is that your vehicle's service facility has the special equipment to recover the refrigerant and check the system's pressure, both vital to properly servicing the air conditioning system.

As with many vehicle components, regular maintenance can go a long way to minimizing problems in the air conditioning system. It can reduce the chance of the compressor having to be replaced, too.  Pretty cool, huh?

Dennis Road Automotive
11155 Dennis Road
Dallas, TX 75229
9722411901