Did that pothole hurt my car? Here’s how to tell
Question: With all the storms we have been having lately, my car has taken some abuse from potholes and from dragging its bottom over rocks, gravel and tree parts. How can I know if the car has been damaged from any of these incidents? How likely is it that damage might happen from dragging bottom or from hitting a huge pothole? How can I tell if I should go to the shop to check or fix damage?
T.K. Answer: It’s hard to give you definitive answers because the undersides of vehicles greatly differ, as do the toughness of their suspension systems and their tire and wheel types. Any damage sustained will also, of course, depend on the severity of the impacts your vehicle incurs.
The overwhelming majority of passenger cars these days are front-wheel drive. Other than the exhaust system and parking brake cable running down the centre of the underside, the centre area of most vehicles is basically a tough metal pan. If one were to drag-bottom on a pile of gravel or loose road debris, the odds of serious damage would be low, unless the catalytic converter were to strike something fairly hard. The front end of the car is generally the most tender, with powertrain parts and other critical parts generally only partially protected by a metal cross-member. The car’s rear underside is also vulnerable, with the fuel tank and muffler susceptible to damage by impact.
Exhaust system misalignment may cause odd noises, but as long as nothing is hanging down or separated, driving further is likely OK. Brushing over debris is probably not too harmful, but actually striking something like a rock or a pavement edge certainly can be. Odd rattling or clanking noises after, or anything visibly disturbed or hanging down, justifies a trip to the repair shop.
A strong pothole strike with a tire or wheel should be followed up as soon as possible with a visual inspection of the tire for possible splitting or tearing. You should also check the rim edge for bending or splitting. Either of these outcomes calls for a possible spare installation, a tow or a trip to the shop. If no visible damage is seen, check to see if the steering wheel is crooked or if the car now pulls to one side. If so, this means suspension or steering damage has occurred, wheel alignment will be affected, and there’s a slight chance of a part failing soon. It’s also possible to have no visible damage or immediate steering issues but to eventually encounter accelerated tire wear.
If you encounter issues like this even occasionally, it’s still a good idea to have the underside of the car inspected during each oil change. While your shop’s at it, also have them check each tire for damage and abnormal wear.
Q: The warranty for our 2010 Kia Rio was up to 100,000 kilometres. At 106,000, the engine light went on and we had the dealership check the problem. It turned out that three of our coils went bad. Could you please explain how important these coils are and if this particular car brand has problems with it?
E.H. A: The coils that failed are the ignition coils. There is one for each cylinder and they create the high voltage needed to make the spark plugs spark. So, yes, they are very important. I am not familiar with any pattern of failures, although it seems that Kia and Hyundai coils do not have as long a life as other manufacturers’ coils.
Q: A little over a year ago, we purchased a used 2010 Dodge Nitro Shock. When winter set in, we realized that the heat did not come out of the floor vents as strong as it did other vents. No matter where you changed the setting to it would not come out the floor vents very strong. On very cold days, your feet can get numb, while your face and head are burning. We replaced an actuator after diagnosing it online. The actuator moves (we tried it before installing it), but it doesn't open the floor vent. The dealer we bought it from wants to put in a new “heater box” to the tune of $1,500. Others say the actuator needs to be calibrated. Your thoughts?
C.F. A: Door actuators need to be initialized after installation and a scan tool is required to do it. The dealer has the equipment, but so do many independent repair shops. Try this first, as it is much cheaper than replacing the whole HVAC box.
Q: When a vehicle is featured in a newspaper article, the description usually includes the make, model, gas mileage, horsepower, features, interior space, length, width and sometimes the price as tested. Generally the description does not include the vehicle weight. Most car enthusiasts know that a quick reference guide to vehicle performance is the weight to horsepower ratio. Is the vehicle weight purposely excluded to conceal this factor for buyer consideration?
J.K. A: I do not think that carmakers are trying to deceive you. It is a matter of how much information is valuable to the greatest number of potential buyers. Besides, the curb weight varies depending on how the vehicle is equipped. Does it have a four-cylinder or six-cylinder engine? Automatic or manual transmission? Is the interior the base or luxury edition? Perhaps you can extrapolate the weight of the car based on its gross vehicle weight rating that appears on the driver's door sticker.