(704) 372-3885 2641 N. Graham St. Charlotte, NC 28206

Learn About Your Car

Your vehicle isn't the only aspect of life with recommended intervals: you have dental cleanings, physical exams, laundry, mowing the lawn and paying the bills.

What would happen if you didn't follow these intervals? Well, you'd get more cavities. You might miss health issues that benefit from early detection and treatment. And you'd wear dirty clothes, be embarrassed by your overgrown lawn and have your utilities shut off.

People realize there are some things in life that we have to take care of regularly. If we don't, there are negative consequences. For drivers who want to be more proactive with their car care, here are some simple ways to remember what has a maintenance interval.

First: Fluids. If it's liquid, it's got a replacement schedule. Oil, transmission fluid, coolant, power steering fluid, brake fluid, differential fluid, etc..Then, think Tires. They need air, rotation, balancing and alignment. And while you're thinking tires, think brakes and shock absorbers. And what makes your vehicle go? Air and Fuel. Air filter replacement, fuel filters and a fuel system cleaning. Of course there are more items, but if you remember to take your vehicle in for these things, we will be happy to help you with the rest.

What if drivers don't follow recommended service intervals? Your fuel economy will decrease, your vehicle won't perform as well, your safety will be compromised and you'll spend more in the long run. Reason enough to follow recommended service intervals.

Today's Joey's Truck Repair Inc. post focuses on the importance of protecting your mass air flow sensor or MAF. Air and fuel are mixed together to be burned in your engine. The amount is controlled by how hard you press on the accelerator or by external factors like climbing hills or hauling loads. Based on how much air you need – and how much is available – your engine management computer tells your fuel injection system how much fuel to send to your engine. But what if the computer is getting the wrong information about how much air is coming into your engine? Well, it would send the wrong amount of fuel and your engine performance would suffer.

The Mass Air Flow (MAF) sensor measures the volume, temperature and density of the air flowing into your engine. With that information, the computer calculates how much oxygen is available to burn and adjusts the amount of fuel it sends. A dirty or damaged MAF sensor can give the wrong readings, hurt your fuel economy, damage the catalytic converter, reduce engine performance, trigger the Check Engine light and, worst case, stop your engine.

Remember that you can drive your car if the Check Engine light is on - unless it's flashing. If your Check Engine light indicates an MAF problem, we recommend that you take action before you damage your catalytic converter.

How does an MAF sensor get damaged? Well, let's look at this process again. As air comes into your engine, it first passes through the engine air filter. Dust, road grime, pollen and other contaminants are, hopefully, trapped in the filter. If the engine air filter becomes clogged, some of the pollutants can pass through and hit the MAF sensor. Thus, a clean engine air filter protects your MAF sensor. Reason number 47 to replace your engine air filter as recommended.

Now if your MAF sensor is contaminated, you may be able to clean it with an air induction cleaning service here at Joey's Truck Repair Inc. This service also cleans your throttle body and other fuel system components. In those circumstances where the MAF sensor is not only contaminated but actually damaged, it will need to be replaced. (And it costs a whole lot more than an engine air filter.)

We will inspect your engine air filter to see if you need a new one. A caution: low-line air filters may actually contribute to MAF sensor failure as filter material can come loose and contaminate the sensitive sensor elements - filter material is just as harmful as outside gunk.

When we recommend you replace your engine air filter, now you know how much is riding on that inexpensive but simple part.

Disc brakes are called disc brakes because of the big metal disc – or rotor – that spins with the wheel. The brake pads rub against the rotor to slow the vehicle. In technical terms, the motion energy of the moving vehicle is transferred into heat energy by the brakes. The job of the rotor is to absorb that heat and dissipate it into the atmosphere. To do that effectively, the rotor needs a certain amount of mass (measured by the thickness of the rotor) and a good surface to mate with the brake pads. Let’s talk about those two things.

First is the thickness. A new rotor is nice and thick. It can absorb a lot of heat and dissipate it effectively. Over time, the rotor will wear away slightly. If it wears away too much, there is not enough metal to take care of this heat transfer, and the vehicle will not brake as well. In fact, each rotor is stamped with the minimum thickness the rotor must have. When the rotor reaches this “discard thickness," it must be replaced.

Next in our consideration is the rotor surface. Now this is not just about the quality of the rotor’s surface but also about how evenly the brake pad sweeps the rotor. Several things can affect the “swept area” of the rotor. A common problem is a scored – or scratched – rotor. When brake pads wear past the point at which they should be replaced, metal parts of the brake can come in contact with the rotors and grind grooves into the rotor. Imagine putting new brake pads on a scored rotor. The pad would only contact the ridges. This can significantly reduce the contact area and hurt braking performance. When a rotor has been scored, it may be able to be resurfaced on a brake lathe which smooths the surface. If the rotor is not thick enough to be resurfaced, it must be replaced.

Another common rotor problem is something called run out. This is when the rotor is slightly off axis (crooked) so the brake pads do not contact the rotor fully and evenly. Run out is measured in thousandths of an inch, so we are talking very small variations that can affect braking. Run out can be caused by a bit of dirt or rust between the brake rotor and the wheel hub, or even by slight variations in the mating surfaces of the brake and hub. Your technician can determine the cause and take the appropriate measures to restore proper brake pad contact.

When run out is not detected and corrected early, the rotor itself can wear unevenly, leading to thickness variations. This condition is called parallelism because the inboard and outboard surfaces of the rotor are no longer parallel. The variations are small, measured in 10 thousandths of an inch, but they can significantly affect braking performance because of limited brake pad contact. This condition used to be referred to as “warped” rotors, but that term is inaccurate. If the rotor is still thick enough, the brake technician will correct the underlying run out problem and resurface the rotor to restore the contact surface. If the rotor is severely worn, it must be replaced.

So if you hear a grinding sound when you brake, get your brakes inspected at Joey's Truck Repair Inc. as soon as you can to avoid possible rotor damage. With run out and parallelism, you may feel a pulsation in the pedal as you brake. If you feel a pulsation or if your pedal feels unusually soft or hard, take your vehicle in for an inspection. Our qualified brake technician, while using quality brake parts can get you safely running – and stopping –as soon as possible.

An oil change at your local auto shop sounds simple, but there are some pretty important things to know about preventing oil sludge.

Oil eventually starts to turn into jelly, literally: petroleum jelly. Sludge clogs up oil passages and keeps oil from getting to some areas of the engine, causing parts to wear out prematurely. And that means expensive engine repairs.

That's why you need to change the oil and oil filter on schedule — to get the old oil out before it turns to sludge. Your manufacturer will have a recommendation for how many miles/kilometers you can go between oil changes. They also usually have a number of months between recommended oil changes. That's because the detergents and other additives in the oil break down over time.

Your owner's manual will have a recommendation for time and distance, but you need to remember that it's based on using the recommended weight of oil. And if your vehicle came from the factory with synthetic oil, the recommended intervals assume you will continue to use synthetic.

Also, how you drive can have a big effect. Most owner's manuals will have a list of driving conditions that are harder on your vehicle — things like stop and go driving in Charlotte, short trips to Charlotte, driving in very hot or very cold weather, heavy loads and towing. If some of your driving fits this, you may need to change your oil and do other maintenance on a shorter schedule.

This may sound complicated. Some vehicles have an oil life calculator that takes all of these factors into account and tells you when you should change your oil. Otherwise, talk with your advisor at Joey's Truck Repair Inc. about how you drive and get his or her recommendation for when to take care of your service.

Finally, if any of the steering or suspension parts can be lubed, your technician will take care of that with a lube, oil and filter service.

Question:

My technician said I need a new serpentine belt but I don't see any cracks in it. Does it really need to be replaced?

Answer:

I appreciate your concern. Old style neoprene belts would crack with age, making it pretty obvious to Charlotte citizens when they needed to be replaced. Nowadays, serpentine belts are made from a different material that doesn't crack or glaze the way neoprene did.

Stepping back, the serpentine belt transfers power from the engine to various accessories like the alternator, power steering pump and air conditioning compressor - even the power brakes and water pump on some vehicles. Modern serpentine belts have several grooves running their length. These grooves mate with the pulleys on the accessories. When the belt is within its useful life, it spins the accessories at the designed speed.

Over time, belt material is worn away. When as little as 5% of the material is lost, the belt can slip and not properly spin the accessories leading to stress and damage.

Using a special tool, your friendly and knowledgeable Joey's Truck Repair Inc. service advisor can measure the material lost in your serpentine belt. He will indicate if it needs to be replaced.

It's for Charlotte drivers to understand that the serpentine belt is part of the accessory belt drive system which also includes the serpentine belt tensioner and any idler pulleys. The belt tensioner has the same service life as the belt itself, so if it is time to replace the belt, you should also replace the tensioner and idler pulleys as well.

A worn belt tensioner can cause belt slip and enough belt-slap to really hammer the accessory upstream from the tensioner. Running too long with a worn belt, tensioner or idler pulleys causes excessive heat at the accessory pulleys, resulting in inefficiency, damage and premature replacement.

We can perform tests to see if your belt or tensioner is worn and should be replaced. Ask your if it's time for a serpentine belt system replacement.

Give us a call to set up an appointment!