Lewisville Auto Repair

Mon - Fri: 7:30 AM - 6:00 PM
Towing Services

Frequently Asked Questions

We have compiled some Frequently Asked Questions that we have been asked time and time again. Click on a question to see the answer.

You’re driving along in your car or truck and suddenly a yellow light illuminates on your dash telling you to check or service your engine. The “check engine” light is part of your car’s so-called onboard diagnostics (OBD) system. Since the 1980s, computers increasingly have controlled and monitored vehicle performance, regulating such variables as engine speed (RPM), fuel mixture, and ignition timing. In some cars, the computer also tells the automatic transmission when to shift.
When it finds a problem in the electronic-control system that it can’t correct, the computer turns on a yellow warning indicator that’s labeled “check engine,” “service engine soon” or “check powertrain.” Or the light may be nothing more than a picture of an engine, known as the International Check Engine Symbol, perhaps with the word “Check” appears on your instrument panel. Come in today for your free Check Engine Light evaluation.

For cars without electronic ignition, built prior to 1981, a tune-up is needed every 15,000 to 20,000 miles. A tune-up consists of replacing the spark plugs, ignition contact points, rotor and distributor cap, and adjusting the ignition and carburetor timing.
Modern vehicles equipped with electronic ignition, fuel injection, and computer controls require an inspection, computer diagnosis, testing, and adjustment in order to keep the engine at peak performance and efficiency and keep exhaust emissions low. Spark plugs, plug wires, sensors, and modules are checked and replaced where necessary. The frequency for tune-ups depends on driving conditions and can vary from 30,000 to 100,000 miles, depending on the manufacturer. Check your owner’s manual or speak with a Lorentz ASA-Certified technician.

If you are driving at highway speeds, and the engine overheats, there is a problem such as a burst hose, low coolant, clogged radiator, or broken belt. To avoid damaging your engine, you must move your vehicle to the side of the road and shut it off for at least 20 minutes. Open the hood to allow air to circulate, but do not ever attempt to remove the radiator cap until the radiator is cool, as serious injury or scalding may occur. If there are no obvious signs of a problem, such as a broken hose or belt, then you may add coolant or water. Due to the extreme heat conditions that often occur in our area, we do not advise you to attempt to drive to a service station when your vehicle is in this condition. Instead, feel free to call us, and we will provide or help you coordinate roadside assistance, including towing if necessary.

You will not be able to tell just by unscrewing the cap and looking at it. Lorentz Certified mechanics have special tools for testing the PH balance inside your radiator. Over a period of time, the ethylene glycol coolant tends to age, break down, and turn into sludge that can have a corrosive effect on your radiator. Coolant is an environmentally hazardous substance and is toxic to humans and animals. Don’t try to change it yourself. Let the professionals at Lorentz handle it for you, to dispose of the waste product safely.

If you are experiencing this problem, turn the air conditioner off and have it serviced as soon as possible to avoid damaging your system. The problem can be caused by a stuck blend door, a clogged condenser, or leakage of refrigerant gas. A certified Lorentz Automotive technician can diagnose the problem and repair it for you.

Talk to an expert at Lorentz about your driving habits. Short local trips, stop-and-go traffic, driving on dirt roads, and severe weather conditions can cause impurities to build up in the oil. These impurities can cause permanent damage to your engine and shorten its useful life due to excess wear and tear. A good rule of thumb is to change the oil and filter every 3 months or 3,000 miles, whichever comes first. Check your owner’s manual for the manufacturer’s recommendations. Keeping clean oil in your crankcase may be the single most important thing you can do to prolong the life of your vehicle and keep it running efficiently.

Check your owner’s manual. Correct tire pressure is also listed on a plate in the glove compartment, fuel door, or driver’s door post. The range of pressure is calculated based on size and weight of the vehicle and type of tires. Pressure may be adjusted somewhat for load hauled and type of driving.

Brakes should not make noise when they operate. A grinding or squealing sound make indicate a need for new brake shoes or pads. Remember that noisy brakes are usually unsafe brakes. Delaying service is dangerous and can increase the cost of repairs later. A Lorentz Automotive technician can diagnose and correct your brake problems.

Automatic transmission fluid and filter should changed every two years or 24,000 miles, especially if the vehicle is more than five years old. Some newer vehicles are built with transmissions that never need servicing.
If your vehicle tows a trailer, goes off-road, carries a camper, or is driven hard, the fluid and filter may need to be changed every 12 months or 12,000 miles; otherwise dirt and moisture buildup in the fluid may cause damage. The harder the transmission is used, the hotter the transmission fluid gets, and the fluids can break down.
Manual transmissions need to be serviced once a year or every 30,000 miles and may need repairs or replacement of worn clutch, throw-out bearings, and broken synchromesh gears. Consult your owner’s manual or talk to a certified specialist at Lorentz Automotive.

Absolutely! An impartial periodic check of your vehicle protects your long term interests, particularly if you plan on keeping your car for a long time. If your car is under warranty, we will prepare a list of any items covered under the warranty that may need attention for you to present to the dealer. An unfortunate fact of life is that most dealer technicians won’t look too hard at your car for defects while it is under warranty. Warranty repairs don’t pay as well as retail repairs do!

An independent automotive study found that a majority of surveyed drivers believed they drove in “normal” conditions when they actually met the criteria for severe or special operating conditions.
Severe 3,000 miles: Factory recommended for special operating conditions including short drives and stop-and-go driving in any temperature (like metro commuting); low speeds for long distance; driving on rough, muddy, snow-melted or salt-covered roads;and any/all of the conditions listed under 5,000 miles.
Tough 5,000 miles: Factory recommended for driving on unpaved / dusty roads ; towing a trailer or using a car-top carrier; repeated trips of less than 5 miles in below freezing temperatures.
Normal/Ideal 7,500 miles: Factory recommended for conditions other than those that require 3,000 or 5,000 mile service.

Lorentz Automotive is committed to ensuring effective communication and digital accessibility to all users. We are continually improving the user experience for everyone, and apply the relevant accessibility standards to achieve these goals. We welcome your feedback. Please call Lorentz Automotive (972) 353-2100 if you have any issues in accessing any area of our website.