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Many vehicles use engines with a specific configuration and valve placement. These motors are known as interference engines.

To understand what an interference engine is you first must understand what is going on within your engine. Inside all engines are valves that allow air and/or fuel into and out of the combustion chambers, camshafts open the valves, your timing chain rotates your camshafts, and your crankshaft rotates your timing chain. The crankshaft rotates due to the up-and-down movement of the pistons. 

An interference engine has a design where the internal valves can extend into the area of travel of the pistons. If the pistons and valves can be in the space area at the same time that means they can hit each other; interfere with each other (hence the name). The valves under normal conditions are never able to be in the area of the piston at the same time. The timing chain is responsible for controlling the movement of the valves and the timing chain spins due to the movement of the pistons.

Since the pistons are responsible for the valve movement, we can design the entire system to control itself and not allow interference. This is one reason why timing is important on an interference engine. As long as the timing chain and timing system are functioning properly the engine has no issue. An interference engine only has a problem when the timing is off.

What Causes Faulty Timing?

What causes an engine’s timing to be off? If the timing chain jumps or breaks you can then have the pistons strike the valve. Let’s start with what happens if the timing chain “jumps”. This means the chain becomes disconnected from the crankshaft sprocket and the sprocket keeps turning. Once the timing chain becomes connected again it is now out of synch because either the crankshaft or the camshaft was able to spin freely while the other did not. Once everything is connected again the shafts will be out of phase. Now the valves will open early or late. Either way, it’s not a good situation. Now the piston is moving up and down while the valves are opening and closing. If the piston is moving up and the valves are still open they will both want to occupy the same space. 

What happens if the piston hit the valves? The pistons have so much momentum behind them that they will bend if not break the valves once they come in contact. The piston is very heavy and cycling at the RPMs of the engine. Typical RPMS are in the 1,000s. So the pistons are moving very fast with a lot of weight. Now the engine has a serious problem. A bent or broken valve won’t seal. This means air can enter and exit the combustion chamber freely. This will make the engine run rough and, in most cases, cause such a loss of power, the vehicle is not drivable. Almost always a check engine light will be triggered. 

The expert ASE-certified technicians at Scott’s U-Save in Steger, IL New Lenox, IL, and Schererville, IN can properly diagnose and repair any engine issue you may have. All of our locations have decades of experience, state-of-the-art diagnostic equipment, and stay up-to-date on training. This allows our technicians to determine the root cause and service the correct part of your vehicle.  We also offer a nationwide part and labor warranty on all of our services. Let the experts at Scott’s U-Save take care of your vehicle and keep you safely on the road by scheduling an appointment today!

When it comes to anything relating to your vehicle, we like to focus on value and not price. The reason why, people use their vehicles on a daily basis and keep them for many years. When it comes to parts or tires it’s an investment and directly relates to your and your family’s safety.

Now, Michelin Tires was founded in 1888 by brothers; Andre and Edouard Michelin. They first began with bicycle tires and then in the 1890s began manufacturing automotive tires. Since then, Michelin has grown to be the most recognized tire brand around the globe. They are also known as the luxury brand tire and we often hear from tire buyers, “Are the Michelin tires worth the money?”.

Simply put, yes, they are. But a better answer may be yes they are but they aren’t always for everyone. Again, we go back to the idea of value and most importantly what type of solution the customer is in need of. 

What you Get with Michelin

Michelin tires are not cheap, and they aren’t priced middle of the road either. But what are you getting when you purchase a Michelin tire? Every Michelin tire comes with the Michelin Promise. This gives you a 60-Day Satisfaction Guarantee, 150 miles of towing if you don’t have a spare, flat tire change, lockout service, battery jump-start, and fluid services. 

Beyond the Michelin Promise, every Michelin tire is a highly engineered piece of equipment designed to keep you safe and maximize the performance of your vehicle. From vehicle to vehicle that performance metric changes, hence why Michelin has a wide range of tires. The price of a Michelin may be higher than other brands you’re comparing, but that price is higher because Michelin invests heavily in its engineering. This focus on research and development is why Michelin is used so often by professional racing teams.

Lastly, there’s the cost of the premium materials Michelin uses in their products. Both raw material costs and manufacturing processes can either add a lot to the cost of a tire or can be neglected to help decrease the cost of a tire. Michelin uses not only top-quality rubber, but many expensive additives like silica to help the tire handle a wide operating temperature range, but they also manufacture their tires with full-depth sipes.

The full-depth sipes give the tire traction in snow, ice, and wet surfaces. Many manufacturers may have sipes that go about 2/32 –  5/32nds of an inch into the tread, but Michelin was the first to develop manufacturing processes that allow for the sipes to do the full tread block (8/32nds of an inch). 

To see the longevity of Michelin’s quality you can find it in their consecutive awards. For 19 consecutive years, Michelin has been awarded by J.D. Power as the top luxury brand. Michelin’s sister company, BFGoodrich, was also awarded the 2021 leading original equipment tire brand for trucks. 

Again, we feel the number one aspect to consider when purchasing tires and repairs for your vehicle is value. Michelin tires are not cheap, but every time you purchase Michelin tires you will always receive a top-quality tire from a company that will stand behind its product.

Now, if the Michelin tires are just simply out of your budget it is good to also look at BFGoodrich and Uniroyal. Michelin owns both BFGoodrich and Uniroyal. All of the R&D and manufacturing breakthroughs that Michelin develops will eventually move their way into the BFGoodrich and Uniroyal brands. A great tire showcasing this trickle-down effect is the BFGoodrich Advantage Control. 

Tires at Scott’s U-Save

Let the tire experts at Scott’s U-Save in New Lenox and Steger, Illinois, and Schererville, Indiana help you with all your tire needs. We’ve been your local tire experts since 1981.

Call or schedule online with us today!

The GM 2.4L Ecotec engine has powered some of GM’s most popular models during the 2010s. From the Chevy Malibu to the Polaris Slingshot, the 2.4 Ecotec can be found in a wide variety of vehicles.

What the 2.4 Ecotec might be most well known for though was its tendency to have timing chain failure. One of the most dreaded issues within an engine, a failed timing chain can lead to irreversible damage down the line if not taken care of immediately.

What is a Timing Chain?

Your engine’s timing chain is what synchronizes the four stages of the engine. The timing chain connects the crankshaft to the camshafts. As the crankshaft spins the timing chain will transfer this rotational enginery to the camshaft or shafts. Some engines have one camshaft while it now has become common for dual camshafts. The engine’s camshaft(s) have lobes that open the internal valves. The timing chain gets its name because it sets “timing” and makes sure events are happening at the same time. 

The engine has four stages, intake, pressure, spark, and exhaust. During the intake stage, at the same time, the piston moves downward while air and fuel enter the combustion chamber. The camshaft has to open the intake valves to allow the air to fill the chamber. Next, the piston moves upward. The valves must close so the piston can increase the pressure of the air/fuel mixture inside the cylinder. Once the piston has reached its highest point we have a spark. The spark plug causes a spark to ignite the air/fuel mixture. Finally, we have the exhaust stage. The valves open and lex the exhaust gas exit the cylinder. The timing chain is responsible for the opening and closing of the engine valves at the proper time based on the movement of the piston.  

You can imagine how much stress a timing chain faces and the amount of friction generated. Oil is of the utmost importance to the life of a timing chain. The timing chain also has guides and tensioners. The accumulation of these components is referred to as the timing system. 

The Cause

The GM 2.4L Ecotec Engine is known for timing chain issues, but in reality, the culprit of this issue are the tensioners. Just like the tensioner for your serpentine belt, the timing chain has two tensioners that put pressure on the chain to stay connected to the sprocket of the crankshaft and camshaft(s). 

If the chain doesn’t maintain connection with the sprockets, it can “jump”. This means the chain becomes disconnected from the sprocket and the sprocket keeps turning. Once the timing chain becomes connected again it is now out of synch because either the crankshaft or the camshaft was able to spin freely while the other did not. Once everything is connected the shafts will be out of phase. This is complicated, but just know the engine’s valves are no longer opening and closing in synch with the piston movement. This means the air and exhaust are not entering and leaving the chamber at the correct time.

How do I Know if my Timing Chain is Bad?

What are the signs of a timing chain issue? You will first notice the engine running rough; typically leading to misfires. The best way to feel this is at idle when the engine is at low RPMs. The end result, the check engine light comes on and you’re not sure what to do next

A timing chain failure can lead to catastrophic issues for your motor. If you feel anything resembling the symptoms, such as misfires, contaminated oil, and trouble starting the engine, you should take your vehicle to a repair facility you trust as soon as possible. 

Timing Chain Service at Scott’s U-Save

Let the expert ASE-certified mechanics at Scott’s U-Save in Steger, IL New Lenox, IL, or Schererville, IN diagnose that check engine light. To test for timing chain issues, we will often use a 4-channel scope to map the sequence of the pistons to the valves. What we are doing is checking that timing within the engine matches each other. 

When we repair a GM that has a failed timing chain, we will replace the entire timing system. There is a lot of labor required to get into the timing chain because you need to remove the front section of the engine. It’s worth it to pay the extra few hundred in parts to make sure none of them fail in the coming years which would require another $1,000+ repair because you again need to remove the front section of the engine.

Call or schedule online with us today!

The GM 2.4 liter engine has been in production for just over a decade. It’s commonly found in the Chevy Equinox and Malibu, GMC Terrain, and Buick Verano. The GM 2.4L engine is a part of the Ecotec engine family. The GM 2.4L Ecotec engine features a direct inject fuel system, variable valve timing, and dual overhead cams. 

While this engine has inherent issues, it does have some positive design features. The engine block has sand-cast cylinders. This casting not only reduces NVH (noise, vibration, and harshness) it also provides rigid strength to the overall engine block. The pistons themselves are manufactured from lightweight aluminum to enhance efficiency and lower mass. The GM 2.4L Ecotec engine is an in-line 4-cylinder design. This design has a small footprint but does produce a decent bit of horsepower; from 164-182. Overall, the GM 2.4L engine was designed for efficiency. 

Why is it so Hard to Diagnose Leaks?

Why are oil leaks hard to determine right away, and why is a visual inspection often not enough to diagnose? Let’s think about what is going on in a vehicle’s engine bay while we drive. The vehicle is normally going above 40 mph, driving in all weather conditions, over dirty roads, and every vehicle in front is kicking up dirt and grime into our vehicle. The engine bay sees a lot. As oil leaks out it gets blown around significantly because of the vehicle’s speed. What this means is a small amount of oil can cover a large area because the oil sprays as it leaks.

Similar to the issue with the oil spraying everywhere, a small amount of oil leaking towards the top of the engine will then run down the engine block and accumulate on the oil pan. Visually, the oil may look as if it’s coming out of the oil pan or the bottom of the engine block. Yet, the oil actually came from above. This is why we start by cleaning off the leaking oil, adding the dye, and determining what is the root cause of the oil leak. 

Rear Main Seal Leak

Now, for the problems. At Scott’s U-Save we see failure of the rear main seal causing large oil leaks. When we diagnose oil leaks at Scott’s U-Save we define the situation as weeping, seeping, and leaking. Weeping is natural with all oil seals. Seeping is when a seal is starting to get old and crack but still maintaining a decent seal. Leaking is when the seal allows enough oil past that it can now accumulate on the bottom of a surface. We see the rear main seal on GM’s 2.4L Ecotec engine fairly often. We don’t see it often below 70k miles. As with all seals it’s not expected to last forever. But specifically on the GM 2.4L LEA Ecotec, we see the rear main seal leaking as a common issue. Most engine’s rear main seals will last the life of the engine.  

How can we tell if the rear main seal is the cause of the engine oil leak? We will often start diagnosing an oil leak with a clean & dye. During this process, we will clean off all the oil on the engine block, oil pan, and other areas. We then put a black light dye into the oil. After driving about 100 miles we will re-inspect the engine to see where oil is coming out and use a black light to find the root cause. 

Timing Chain Issue

We couldn’t talk about the 2.4L without at least mentioning the timing chain. The GM 2.4L Ecotec engine’s timing chain is the most common problem for these engines. We have another blog post specifically explaining this issue. It should be noted GM did update parts on newer 2.4L engines to help with the tensioners. Lastly, the GM 2.4L Ecotec engine is an interference engine. Yet another concern with this engine design. You can find out more about these engines in this blog:

Carbon Buildup

A minor problem to note is since the GM 2.4L Ecotec engine uses a direct injected fuel system we do see issues with carbon buildup. This can cause rough idle, check engine light, and power loss. Again, we wouldn’t necessarily say this is a common issue to only the 2.4L engine. This issue is common to any direct-injected engine that is not properly maintained. So, for this issue, we highly recommend owners regularly perform fuel services every 30-45k miles and don’t delay oil changes. 

Finally, a common issue similar to the carbon build-up is oil consumption. We’ve rarely seen a 2.4L engine with failed piston rings. We’ve also seen oil consumption past the engine valves. We do feel this issue is most often related to not properly maintaining a direct injected fuel system. It is worth noting GM has had lawsuits over oil consumption. So, this is enough of a problem for lawyers to get involved. 

Tire maintenance is a crucial aspect of vehicle care that is often overlooked. Many owners wonder when it’s time to bring their car in for a tire rotation. In this article, we’ll dive into the importance of tire rotation, when it’s best to do it, and why this service is essential for the longevity and performance of your tires.

What is Tire Rotation?

Tire rotation is the process of moving tires from one position on a vehicle to another. This practice helps ensure that the wear on your tires is evenly distributed, which can prevent uneven tread wear and extend the lifespan of your tires. Uneven tire wear can lead to poor traction, reduced fuel efficiency, and even safety risks. Tires with excessively worn tread will lack the traction to keep you safe in inclement weather or evasive driving. 

Tire Wear

Many vehicles only deliver the power from the engine to two wheels, either the front two or the rear two. Even on all-wheel drive or four-wheel drive vehicles, slight differences in the wear of each tire can create problematic uneven tread wear. 

Why do I Need to Rotate my Tires?

There are several reasons why tire rotation is crucial for maintaining the health of your tires. First and foremost, it helps ensure even tread wear. Tires tend to wear down more quickly on the front axle due to the strain of steering and breaking. Rotating your tires allows for more even wear across all four tires, helping to extend their lifespan.

Secondly, tire rotations can improve the performance and safety of your vehicle. Unevenly worn tires can impact traction and handling, especially during adverse weather conditions such as rain or snow. Regularly rotating your tires can help ensure a safer driving experience.

Tire rotation can also save you money in the long run. Tires are a significant investment, and getting them rotated regularly can help you maximize their lifespan. By avoiding uneven wear, you can prevent the need for premature tire replacements, which can be costly. Tire rotation is a small investment that can lead to significant savings by prolonging the life of your tires.

How Often Should I Rotate Mine?

So, how often should you rotate your tires? Most experts recommend getting your tires rotated every 5,000 to 7,000 miles, or every six months, whichever comes first. However, there are some additional considerations to keep in mind. 

If you notice any signs of uneven wear on your tires, such as your vehicle pulling to one side, or if you have recently replaced one or more tires, it’s a good idea to get a tire rotation done as soon as possible. 

Additionally, if you’re planning a long road trip or will be driving in harsh conditions, it’s best to have your tires rotated before leaving for your journey to ensure optimal performance.

Properly Rotating Tires

It’s important to note that tire rotation should always be done in a specific pattern recommended by the vehicle manufacturer or a trusted mechanic. The most common rotation patterns are the forward cross pattern and the rearward cross pattern. These patterns involve moving the front tires to the back and vice versa, as well as crossing them to different sides of the vehicle to ensure even wear.

Regular tire rotation is essential for maintaining the health, performance, and safety of your tires. It’s best to follow the manufacturer’s recommendations or consult with a trusted mechanic for the most suitable rotation interval for your vehicle. By ensuring even tread wear, improving traction and handling, and prolonging the life of your tires, you can save money and have a safer and smoother driving experience. Don’t overlook the importance of tire rotation in your vehicle maintenance routine!

Tire Rotation at Scott’s U-Save

If you’re in the Chicagoland area and need your tires rotated, look no further than Scott’s U-Save! We have locations in Steger, New Lenox, and Schererville, all equipped with the expertise and equipment to properly rotate your tires and have you back on the road in no time!

Come see why we’re the trusted name in the community, and call or schedule online with us today!