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Mon-Fri:  7:00AM – 5:00PM
Sat-Sun:  Closed


7126 Amethyst Ave
Rancho Cucamonga, CA 91701

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Engine Repair Rancho Cucamonga, California

Reasons Why Your Check Engine Light Might Be On

Every vehicle owner hates the day that their check engine light comes on. It could be something small, or it could mean that you need an expensive vehicle repair. Modern-day vehicles are made run with little problems if they are properly maintained, but periodic mechanical issues still do occur. If your check engine light does come on one day, you might be tempted to ignore it. After all, as long as your car or truck is still running you should be okay to drive it, right? Not exactly. Your check engine light appears when part of your vehicle needs some attention. Sometimes it’s minor, but other times it could be a serious problem waiting to happen.
To avoid a costly car repair, it’s in your best interest to get to the root of your check engine warning as soon as possible. Bring your vehicle into AI and Sons auto shop and we will diagnose the problem for you. We are the most trusted auto repair shop in the city. No automobile repair service is too big or too small for our dedicated team of mechanics. Here are some common reasons your check engine light might come on:

A Loosened Fuel Cap

That’s right, sometimes your check engine light might come on for something as simple as a Loosened fuel cap. When you pump gas into your vehicle, you may accidently leave your fuel cap on too loose, or neglect to close it at all. When that happens, your check engine light might come on as a way to warn you that you need to tighten your fuel cap appropriately. Other times, your fuel cap may be worn to the point that it does not tighten properly. In this instance, simply swapping your fuel cap should take care of the problem. If a loose fuel cap is the cause of your check engine light coming on, you can easily remedy the problem yourself without the need of an auto repair service professional.

Oxygen Sensor Malfunction

The oxygen sensor in your automobile is responsible for detecting the presence of oxygen together with carbon dioxide being released through your vehicles exhaust. When the sensor detects oxygen, it will regulate your fuel in such a way that combustion is improved to help avoid engine jerking. If your oxygen sensor fails, your car may still seem to be running normally. However, you may soon find that you’re experiencing fuel efficiency issues as your automobile runs through gas at a faster pace. What’s worse, certain components within your engine, such as your catalytic converter, might begin to deteriorate.

Catalytic Converter

The function of a catalytic converter is to minimize the amount of carbon monoxide released into the environment by your vehicle. Carbon monoxide is incredibly harmful to the environment, so your catalytic converter converts it into carbon dioxide instead. If you are great about getting routine maintenance performed on your automobile, you will likely never have a problem with your catalytic converter. However, if you’ve neglected to have your car checked by a professional mechanic on a regular basis, it may fair and cause your check engine light to come on.

Vacuum System Issues

Your vehicles vacuum system serves several different purposes. Your brake booster is operated by a vacuum, for example. But your vacuum system is also used to keep harmful emission levels down by filtering the fumes that are generated when fuel evaporates within your engine. Sometimes, your vacuum system can experience a leak which renders it unable to perform these vital tasks within your engine. Vacuum leak repairs are a relatively simple car service, however, if left unchecked a leaking vacuum could lead to bigger problems.

Spark Plug Malfunction or Malfunction

Your car relies on your spark plugs to ignite properly. Spark plugs emit electricity that initiates an ignition that is needed for combustion and the burning of fuel. Spark plugs can go bad over time, causing them to lose their ability to generate the high volt electricity needed for them to work appropriately. When this happens, you will typically notice that your vehicle vibrates when you come to a stop light or if you’re in slower traffic. In some cases, your car or truck may spontaneously shut down together. Looking into your check engine light right away could help you avoid these problems. Your trusted mechanic at AI and Sons can quickly replace your worn spark plugs to make sure you’re not left stranded at a stop light.
Another problem that might cause your check engine light to come on is damage to the wires attached to your spark plugs. Like the spark plugs themselves, these wires can become worn and need swapping to keep up engine performance.

Mass Airflow Sensor

You mass airflow sensor is different from your oxygen sensor but still does a vital function in your vehicle. This sensor is responsible for measuring the total about of air that enters into the combustion chamber of your engine. From there, it will determine the proper air to fuel ration necessary for your engine to run smoothly. When this part of your engine fails, it could lead to issues with your spark plugs, oxygen sensor, and catalytic converter. Other than your check engine light, you may not know that your mass airflow sensor is experiencing a problem until further occurs.

The best way to avoid an unexpected trip to the auto shop is to have scheduled maintenance checks, oil changes, and other routine automotive services performed on your vehicle by a reputable auto shop. If your check engine light does come on, be sure to bring it in to the trusted mechanics at AI and Sons right away. We will quickly diagnose the problem and give you a fair and honest quote for your automotive repair. From breaks, to transmissions, we pride ourselves on giving all of our customers top quality auto service at affordable prices. Come find out for yourself why we stand out above the rest of the auto shops in town. [/text_divider]

Why us?

Al & Sons Automotive!

Al and Sons Automotive has been in business for over 50 years. We are a full-service auto repair shop and we are trusted by our many customers.

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  • Serving Rancho Cucamonga for over 50 years
  • Computer Diagnostic check
  • No Appointment Necessary
  • Tow Service Available
  • Tire, Brake, and Transmission service
  • Battery Replacement
  • Diesel vehicle service
  • Great Service! Great Honest Prices!

    Jay F.

    They service all of my company vans at The D Jay Company and i have also taken my wife's Mercedes there too for services. Johnny and the staff have been the best and also did a complete engine replacement in one of the company Vans last year ...Great Service! Great Honest Prices!!!

  • This is a business I recommend often and proudly.

    Tom T.
    I was checking the reviews for another shop that is working on my truck, I wish it was at Al and Sons but circumstances are what they are and I hope all goes well for me.   Anyway I thought I'd give a quick nod to Johnny and his team at Al and Sons who have been taking care of my family's vehicles for 30 years. There have been plenty of occasions where quick fixes were done at no charge and situations like with my daughter-in-law where they could have taken advantage of a situation but sent her on her way at no charge instead.  This is a business I recommend often and proudly.
  • One word: LIFESAVER!

    Parisa T.
    One word: LIFESAVER! On our way to Vegas and of course our A/C stopped working. So we tried to tough it out but couldn't handle it any longer . We found this place and it was truly a blessing! Three girls all dolled up for Vegas in a body shop is usually scary but they were awesome!
  • I bring my car from a different city just to use this shop.

    Jim J.
    I started using these guys about 15 years ago when a bunch of other mechanics could not figure out what was wrong.  They diagnosed it right away, and I have not been anywhere else.  I bring my car from a different city just to use this shop.  They are the best!
  • I'd recommend them to anyone looking for a mechanic they can trust!

    Annie G.

    My van's air conditioning went out. Originally we were only going to get an estimate on the cost to fix it (we assumed it was going to be a major cost). My husband found Al's on yelp and we were totally expecting them to come back and tell us it was going to be major work. I also expected them to tell me I needed to have work done on my brakes or engine, which is usually the case when I take my van to Firestone, and they try to pressure me into getting other work done.  Not the case here! They fixed my air conditioning for $155 and said if there were any other problems with it to bring it back. No problems with my AC!

    I love that they didn't totally try to take advantage of our situation. We told Johnny our van is our only car, and he was able to get everything done within a day and a half. I will come here any time I have an issue with my car, and I'd recommend them to anyone looking for a mechanic they can trust!


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We offer computerized diagnostics

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