Ask a Technician: What Should I Do When the Warning Light on My Dashboard Comes On?


Q. The warning light came on my dashboard, should I panic and drive straight to the mechanic?

A. First, don't panic. The "check engine" warning light is simply a general alarm. How it looks and what it means varies from car to car. It might be a yellow or red light or just a little engine symbol. No matter what it looks like, all it lets you know is that the computer that monitors your car has determined that some component of your car is not working properly.

That problem can be a minor one or a major one. It could indicate something as simple as a loose fuel cap, especially if you've recently refueled. Stop the car in a safe place, turn off the engine, and tighten the gas cap until you hear two or three clicks. Sometimes, that does the trick. But if it doesn't, you need to take your car in for a diagnostic evaluation. Don't worry; they're generally painless.

As a [client] general rule of thumb, if your check engine light comes on and stays on, you should take your car to a mechanic. If, however, the light blinks on and off with a regular pulse, it can be a sign of something much more serious. You should pull over when it's safe to do so and have your car towed to the mechanic.

Ask a Technician: Do I Need to Replace My Entire Windshield If It Gets Cracked?


Q. A rock hit my windshield and made a mark but not a-full blown crack.  Can I really just do that crack repair treatment instead of replacing the whole windshield?

A. The basic rule of thumb is that if the chip is smaller than the size of a quarter you can go with a repair job. But if it's any bigger, a replacement might be necessary.

Windshield repair is actually pretty amazing and when done properly, you can barely notice it. Windshield glass isn't your run-of-the-mill glass. It's not like the glass in your windows at home; it's laminated safety glass. Laminated glass is really just what it sounds like - two pieces of glass laminated together with a piece of plastic between them. That inner layer is what keeps the glass in one piece when it breaks. Instead of shattering into tiny, deadly shards, the plastic layer holds the broken pieces together, resulting in that spiderweb look.

Repairing a ding or crack is done by injecting a clear resin into the damaged area and then curing it, usually with Ultra-Violet light, then polishing it back to clarity. There are even over-the-counter kits for the DIY enthusiast. But it's best to have a professional do the work. If you've bought a new car, our service department should be able to do the job well.

Ask a Technician: How Often Should I Change My Cabin Air Filter?

Q. How often should I change my cabin air filter?

A. Drivers and their passengers spend a significant amount of time inside their cars. The automotive industry has been quick to account for this, equipping more and more [client] vehicles with air filtration systems as standard. This is undoubtedly a good thing, but it presents drivers with something else to think about as part of a general auto maintenance schedule.

Air filters are used in most cabin air conditioning systems to filter out particles and pollutants in the air that is drawn into the vehicle. According to the make, model, and specification of your car, your air filter may be designed to trap soot, dirt, and pollen. Even larger items, such as leaves, dirt, insects, and debris from the road can find their way into your air supply, and air filters will protect this from happening. As well as reducing the quality of the air in the cabin, these pollutants can reduce the performance of your heating, cooling, and air conditioning system.

You cannot assume that your vehicle is equipped with a cabin air filter, and if it is, it may not be as easy to find as you would imagine. Your owner's manual should include details of this, but if in doubt, you can also consult the servicing department at your local dealership.

It is critical to ensure that the cabin air filter is working at its optimum performance for as long as possible. The life of your air filter will depend on a variety of factors. Of course, the more that you use your air conditioning system, the quicker your filter may become clogged or dirty. Driving conditions can also affect this. Hot, dusty, rural locations, for example, will greatly accelerate the decline of your filter due to grass pollen, dust, and other particles. As the filter becomes clogged, the system becomes less efficient, meaning that more pollutants make their way into the cabin air supply.

Guidelines on the frequency with which your filter should be replaced vary according to the source of advice. The owner's manual in your vehicle will provide the manufacturer's guidelines, along with any other factors to consider. If you don't have the manual (or if there are no details within it) you should consult the service department at your dealership. General guidelines indicate that such filters should be changed every 12,000 to 15,000 miles of driving, subject to the sort of conditions in which you normally drive. Regular inspections can give a visual indicator of the condition of the filter too, although you may need to ask for your dealer's advice to ensure that you do not damage the filter when inspecting it.

Cabin air filters can be replaced at a relatively inexpensive cost, so it is worth ensuring that it is changed at regular intervals to maintain the performance of your air conditioning system and the quality of air in the car's cabin.

Ask a Technician: Should I Opt for Premium Gas?  

Q. My owner's manual says that regular unleaded is fine for my vehicle. Would it be better for my car if I splurged on premium gas or is that an unnecessary waste of money? 

A. Save your money. If your owner's manual recommends regular unleaded, then regular unleaded is perfectly fine. You're just wasting precious pennies if you pay for a higher octane fuel. Most of today's cars, with the exception of high-performance engines, are tuned to run on regular unleaded fuel. And there's no advantage to be gained by using premium. 

Here's the Skinny

Your engine's cylinders hold a mixture of gas and air. The cylinder compresses that mixture very quickly and your spark plug ignites it. That little explosion (like a cannon firing) is the combustion in an "internal combustion engine" and creates the energy to make your car go. The octane of a gasoline tells you how much compression it can stand before it ignites spontaneously. The higher the octane, the higher the compression it can take. 

Most cars have an eight-to-one compression ratio, which is perfect for regular unleaded gas. That means the cylinder is compressing the gas/air mixture at just the right rate. 

If the gas isn't a high enough grade for the compression rate of the cylinder, it'll ignite early, before the spark from the spark plug. And that's bad for your engine. Those early explosions result in knocking and pinging. So, if you don't hear any knocking and pinging, you're using the right grade of gas. If you do hear those sounds, try upgrading to a premium gas. But, for most cars, using a premium gas doesn't give you or your engine any advantage.   


Lynch Ford - Mt. Vernon Inc.

410 Business 30 SW
Directions Mount Vernon, IA 52314

  • Sales: (319) 895-8500
  • Service: (319) 895-8500
  • Parts: (319) 895-8500

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