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Car Emission Control – Helpful Tips for passing Smog Test

Emissions testing, also known as a smog check, is required in many parts of the country.  The procedure helps ensure your car emission control meets the policies of the Environmental Protection Agency (EPA) and state governments.  Exactly how often your vehicle must be tested depends on the state or local government’s requirements.  The same goes for which model year is exempt or subject to emissions testing.

There are two basic types of emissions tests: tailpipe and onboard diagnostics (OBD II).  Which one your car must undergo depends on the requirements in your area and the age of your vehicle.

  • With an OBD test, a scan tool is plugged into the vehicle’s diagnostic port.  That allows the technician to communicate with the onboard computer to flag any emissions-related problems.  OBD tests are only performed on the model year 1996 and newer vehicles.
  • On the other hand, a tailpipe test requires inserting an exhaust gas analyzer into the car’s tailpipe.  The analyzer measures the levels of hydrocarbons (HC) and carbon monoxide (CO), both of which are pollutants, as well as harmless carbon dioxide (CO2) and oxygen. Many locations also check levels of the pollutant oxides of nitrogen (NOx).

It’s worth considering that a visual inspection is part of the emissions test (both tailpipe and OBD) in most cases.  During the examination, the technician checks to be sure the car’s emissions equipment is intact.  Additional items, such as the gas cap, may be inspected as well.

Tips & Tricks for Passing an Emissions Test

The requirements for passing a tailpipe test are different from those for passing an OBD test.  Therefore, each has a distinct set of preventative measures you should take before test day.

  • Passing a tailpipe test
Car Emission Control

If a tailpipe test is required where you live, you can take a few steps to ensure a favorable outcome.  While these measures won’t guarantee your car will pass, they will give you a leg up on test day.

  • Warm-up your engine

Before getting your car tested, drive for at least 20 minutes to warm it up.  You should schedule an appointment with the testing center to be accommodated while your engine is still warm.  Doing so will help ensure both the engine and catalytic converter are at the optimum temperature for testing.

  • Make sure your car is up-to-date on routine service.

Following the manufacturer’s recommended maintenance schedule helps keep your vehicle running at its best.  The plan includes procedures such as fluid changes, filter replacements, and tune-ups, all of which can affect emissions test results.

So, before you visit the emissions station, be sure your car is up-to-date on routine service.  An outline of the service schedule is located in your owner’s manual.

  • Fix any known engine-related problems

If your engine is working rough, stalling, or exhibiting any other problems, you’ll want to fix the issues before getting an emissions test.  The reason being, engine-related issues often lead to an increase in tailpipe emissions.

  • Make sure the Engine light is off.
Car Emission Control

The emissions test will not pass with an illuminated check engine light.  If the light is on, you’ll need to get the problem that triggered it before testing.

  • Passing an OBD test

You’re in luck if your location only requires an OBD test.  There are just a couple of things you’ll need to check before heading to the emissions station.

  • Ensure that the “Check Engine” light is off

Once again, your car will not pass an emissions test if your “Check Engine” light is illuminated.  Make sure to address this issue and resolve the triggered problem before you go in for testing.

  • Ensure all the monitors have run

Your car’s computer runs self-tests known as “monitors” on emissions-related systems.  During an emissions test, a smog technician will check that all (or nearly all, depending on local requirements) of these monitors have “run” successfully.

The monitors are reset whenever the battery is disconnected.  Clearing diagnostic trouble codes (DTCs) from the computer’s memory also reset the monitors.  If either has been done to your car recently, you’ll want to be sure the monitors have run before emissions testing.  If they have not, your vehicle will be given a “not ready” test result, rather than passing or failing.

Car Emission Control

You can check whether the monitors have run using a scan tool or code reader if you have one.  Otherwise, you’ll want to drive the vehicle at various speeds (both on city streets and the highway) for an extended period.  This way, there is a better possibility of being ready for emissions.

How long does a smog check take?

A smog check typically takes more or less 30 minutes.  It can depend on the number of vehicles in line and whether you could schedule your vehicle for an appointment ahead of time.

What causes a failed emissions test?

Have a professional troubleshoot your car if it fails the emissions test.

There are countless reasons why your car could fail an emissions test that requires a professional diagnosis.  Here are some examples of what a technician might find during troubleshooting:

  • Engine and transmission problems

Problems with either the engine or transmission can lead to an increase in tailpipe emissions and an illuminated “Check Engine” light.  The result is a failed emissions test.

  • Emissions equipment failure
Car Emission Control

Modern cars have an array of emissions equipment onboard.  A few examples include the catalytic converter, exhaust gas recirculation system, an evaporative emissions system.  Problems with such equipment can easily cause your car to fail an emissions test. You can visit The Auto Parts Shop and place an order for affordable automobiles.

  • Module and sensor issues
Car Emission Control

Today’s vehicles contain an expansive collection of computers (referred to as modules and sensors).  Issues with these electronics, their wiring or data network, can lead to a failed emissions test.

  • Air/fuel delivery problems

Your car’s engine requires a precise mixture of both air and fuel to run correctly.  If either of these ingredients is thrown out of whack, there’s a good chance your car will fail its emissions test.

  • Ignition system concerns

The ignition system contains the components that ignite the air/fuel mixture inside the engine.  A complication with any of these parts can create an engine misfire that leads to a failed emissions test.

Car Emission Control

If you cannot afford the necessary emissions-related repairs, some states offer financial assistance to help out.  Investigate with your local government to figure out what’s available in your area.

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Everything You Need to Know About Car Ignition Coil Replacement

As your car grows old, it demands constant repairs. So now if you are facing issues with the ignition coil, you need to get it replaced. There might be several queries popping up in your mind like how much time will it take to replace? You would be looking for an estimate of the repair costs. Let’s learn everything you need to know when it comes to car ignition coil replacement.

Function Of The Ignition Coil

What is the purpose of the coil? The ignition coil acts like a high voltage low current transformer that gives electricity to the spark plugs that can ignite the fuel-air mixture and start the engine. It is one of the essential components of the ignition system as your car won’t start without it. Also, your engine might suffer from difficult starting conditions or sudden stalling.

car ignition coil

When your car fails to start, it probably appears to be a problem in the engine. However, sometimes the issue could appear in the ignition coil, and one must always check it before getting into the engine. 

Car Ignition Coil – Testing

How to check if your car ignition coil is failing? Well, either you can reach a mechanic, or you can determine the same by performing a simple test.

car ignition coil
  • Get a digital ten megaohm impedance the ohmmeter and connect it to the negative and positive terminals of the ignition coils. Read off the numbers that should be between .04 and 2 ohms. If the ohmmeter reads zero resistance, that means the coil is short, and if it reads high resistance, that means the coil is open. 
  • Another way to figure out the car ignition coil replacement is by using a spark tester. Please turn off the engine first and then disconnect the coil from the spark plug, connecting its top to the one end of the spark tester and the other end to the coil output. Now, start the engine. If the light flashes on the spark tester, it means that the ignition coil is working correctly. In case no light appears, it denotes that you have faulty ignition coils that need to be fixed immediately. 

Signs of Bad Ignition Coil

As you now know that without ignition coils, your car won’t start. Therefore, you must be aware of the signals of a bad ignition coil. The most common problem is the misfires. It needs to be addressed as it could damage other parts of the engine.

In modern engines, each cylinder has multiple spark plugs. The ignition coil is connected directly or through special wires to each of these spark plugs. Thus in case ignition coils are not working, it would mess up the entire system. 

Here are some of the most common symptoms of a bad ignition coil.

Engine Backfires: 

Engine backfires are easily recognizable before the ignition coil deteriorates. Before that, are you aware of what happens during engine backfiring? Well, it is the unused fuel leftover in the internal combustion cylinder that starts flowing in the form of black smoke through the exhaust pipe. 

car ignition coil

The smell of gasoline also indicates a problem with the ignition coil.

Engine Stalling:

While driving a regular route at nominal driving speed, if you notice your engine stalls after a couple of miles, it indicates terrible car ignition coils. The stalling happens because the ignition coils do not supply regular current to the spark plugs. For the smooth working and running, the car requires constant current and its absence would completely stop the vehicle causing further damages. 

Engine Light: 

There is a check engine light that turns ON if there is a problem in the car engine. This notification is mostly related to the ignition coils demanding immediate action. When there are issues in the ignition coil, your engine light starts blinking as they are directly connected. Take care of it and get your car ignition oil replacement.

car ignition coil

Loud Engine Noise: 

Have you been noticing excessive noise from your car engine? These are all the symptoms of lousy ignition coils as when they are not able to generate enough voltage for the spark plugs; your engine works harder to continue to run. Since it is overworked, it starts making loud sounds and vibrations.

Poor Fuel Economy: 

Faulty ignition coils won’t pass enough electricity to the spark plugs that would make the engine use more fuel. It would eventually drop your gas mileage. 

car ignition coil

Car Doesn’t Start: 

Your car engine might not start at all if your ignition coils aren’t working with full capacity. It makes a clicking sound.

Car Ignition Coils Replacement

Once you get to know that your ignition coils are not working correctly, you need to find the correct tools to replace them. If you cannot do it by yourself, you can visit your nearby mechanic. 

car ignition coil

Replacing on your own: Disconnect the car battery and then using the wrench, unscrew the bolts and remove the negative terminal. You can find the ignition coils on the top of the engine. Remove it using the wrench and then disconnect the electrical connectors. 

Now, install the new ignition coils. Make sure to bolt tight and reconnect the electrical connections. Put everything back together in its original way. 

Lastly, reconnect the battery’s negative terminal. Start your car and take a test drive making sure that there is no misfire or stalling. This smooth-running ensures that you are successful in installing the ignition coils.

Cost of Replacing The Ignition Coil

Getting your car continuously repaired adds up to higher costs. It is better either to replace the ignition coils on your own or to get it done from a mechanic for which you will need to pay labor costs. 

The cost of fixing the ignition coil runs between $265 and $375, including the cost of labor and the auto parts. The work usually costs from $99 to $125. Therefore if you replace it on your own, you can save a lot. The auto parts cost you between $165 to $250, and the rest it all depends on which part of the ignition coil requires replacement.


Car stalling or misfiring are the signs of a faulty ignition coil. If you notice such issues, you need to resolve these problems with the car ignition coil immediately as it can further damage your car engine to the extent that your car will stop working altogether. The Auto Parts Shop takes pride in selling auto parts at the best prices. Contact us today and get rid of expensive repair bills.

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Why are My Car Headlights and Dash Lights Flickering

Driving with a flickering headlight can create unsafe conditions on the road because they can create distractions for you and other drivers.

If you are wondering why your car headlights and dash lights flicker when your car is running, then you are on the right page.  There are many reasons why your car headlights may be flickering.

What are flickering headlights?

Generally, flickering headlights are caused by a false bulb or a problem in the headlights circuit.

A broken light bulb usually causes flickering headlights.

If your headlight lens shows off while driving, here are the most common reasons:

  • Failing bulb

If you have halogen bulbs, the flickering may be caused by the filaments being damaged or worn out.

Car Headlights and dashlights

Most often, this is a publication signal that your headlight is nearing the end of its life.

There are different types of headlight bulbs, each with an expected life.  Halogen headlights usually burn hot, typically have a shorter service life, and will fail faster than others.  If you have an older vehicle or even a newer, mid-priced model, you probably have halogen bulbs in your headlight.

High-end vehicle models are often equipped with light-emitting diodes (LEDs) or high-intensity discharge (HID) lights, which tend to last much longer.

  • Headlight circuit problem

Flickering headlights may also be caused by a circuit problem.  For example, the issue may indicate damaged wiring or a bad connection.  It may also be to blame a bad headlight switch or relay.

Car Headlights and dashlights

The headlight switch for older vehicles includes a built-in circuit breaker, and when it comes to a short circuit, this can cause the car headlights and dash lights to flicker.

That is why flickering headlights are mostly common with older models.

  • Weak battery

Your car battery usually starts showing up the signs when it is near the end of its life – one of them may be flickering headlights.

A weak battery might not have sufficient power or capability for your headlights so they will eventually dim or flicker.

In general, car batteries can last around 3-5 years.  Several factors can affect the life of your battery, such as the condition of your vehicle, your driving habits, or the weather conditions where you live.

Car Headlights and dashlights

If there is nothing wrong with your bulbs or headlights, you can check the battery for issues as it might be the time for your car battery replacement.

A weak car battery can cause dim headlights.

  • Failing alternator

A problem with the voltage regulator, which is often located inside the alternator may cause the car headlights and dash lights to flicker. Such problems with the charging system may lead to inconsistent current output, which may dim your headlights.

If you blame this component, you will probably observe a few other common symptoms that point to a bad alternator.

Car Headlights and dashlights

It is important to diagnose this problem immediately, so you or your mechanic can fix your flickering headlights as soon as possible.  If you lack technical knowledge or DIY skills to solve the problem, it is recommended to leave this job to a professional.

Diagnosing your headlights

As previously discussed, flickering headlights can be caused by one of several potential factors.  Once you’re excluding the battery and the alternator, there are other ways to diagnose your flickering headlight problem:

Visual inspection

The first and foremost action that you should be performing is to have a visual inspection.  Look for issues, such as:

  • Damaged wiring
  • Burnt out light bulb
  • Damaged headlight socket (s)
  • Independent electrical connections

Use a Scan Tool

Car Headlights and dashlights

If you have the DIY skills  and a scan tool, you can diagnose a broken headlight by following the below steps:

  • Rotate your headlights using your scan tool with the bi-directional command.  If they ignite, this means that the problem is not in your headlight.  The problem is most likely related to the control input to the specific controller that controls the headlight.
  • Determine the location of the open circuit by checking the voltage in different parts with the schematic for the headlight circuit.  Make sure you always follow your repair manual.
  • If your headlights appear brighter than normal, the problem may be related to a high battery voltage.  Check the charging system voltage and make sure it is less than 15.5 volts, which is the standard for most vehicles.  You can check the information to find the exact description.
  • If your headlights are dim as usual, this could be a sign that there is excessive circuit resistance, such as a loose electrical connection, a corroded socket, or a bad electrical ground connection.

You can diagnose your car headlights by either of the above two ways – a visual inspection or a scan tool.

Flickering headlights can cause accidents on the road.  If you notice that your headlights are not working properly, do not waste time, and immediately address this problem. You can place orders for the high-quality car headlights and dash lights at The Auto Parts Shop. You and your passengers’ safety should always come first.