O'Fallon Auto Repair

We've see it. A customer comes in with a check engine light, a rough idle, or a noticeable loss of power, and they tell us they have been trying to fix it themselves with over-the-counter fuel additives from the local parts store. It is a tempting solution. The bottles are relatively cheap, and they promise dramatic results like increased horsepower and better fuel economy. But the reality is often much more complicated, and we are here to shed some light on why you should be cautious before pouring that bottle into your gas tank. The shelves of your local auto parts store are lined with a dizzying array of fuel additives, each with bold claims about cleaning fuel injectors, removing water, and restoring lost performance. While some of these products are not necessarily harmful, many are simply not strong enough to address the severe carbon buildup found in modern engines, particularly Gasoline Direct Injection (GDI) engines. The truth is, the fuel we buy at the pump already ... read more

Here in O'Fallon, we know a thing or two about the challenges our local drivers face with modern diesel engines. While these powerplants offer incredible torque and longevity, the emissions equipment attached to them can be a source of constant frustration. At the heart of many diesel driveability complaints lies the Exhaust Gas Recirculation (EGR) system. It is a critical component designed to reduce harmful NOx emissions by recirculating a portion of exhaust gas back into the engine's intake, but this process comes with a nasty side effect: massive carbon buildup. Why do they get dirty? Diesel engine EGR systems operate under extreme conditions and can quickly become clogged with carbon deposits that affect the fuel economy and performance of a vehicle. If you have noticed a sudden drop in fuel efficiency or your diesel seems to have lost its usual get-up-and-go, these deposits are likely the culprit. We see it all the time. Carbon deposits can cause the EGR ... read more

The Silent Struggle: Conquering Carbon Build-Up in Modern GDI Engines If you own a modern vehicle, there is a good chance it is powered by a gasoline direct injection (GDI) engine. These powerplants are celebrated for their impressive fuel economy, increased power output, and reduced emissions. However, here at Hillside Auto Repair in O'Fallon, we see a hidden consequence of this advanced engineering that often catches owners off guard: the dreaded carbon build-up. It is a mechanical menace that can rob your vehicle of performance and lead to costly repairs down the road if left unattended. We deal with this issue so frequently that we have made it a priority to educate our customers before it becomes a crisis. Why does this happen? To understand why this happens, we need to look at the mechanics of how a GDI engine operates. In older, traditional port fuel injection (PFI) engines, fuel is sprayed into the intake port, upstream of the intake val ... read more

A driver is cruising down Highway K or navigating the streets near the Meadows, and suddenly, that amber ABS light pops up on the dashboard. It is a moment that often leads to a sense of dread. We have had countless conversations with customers who immediately wonder if their vehicle is about to break down or if they are facing a repair bill that will ruin their week. The good news is that the ABS light being on does not necessarily mean your brakes are completely dead. However, it is a serious warning that should never be ignored, especially with the unpredictable weather we experience in Missouri. What is ABS? Before we get into the specifics of what that light means and the dangers it presents, we should explain what ABS actually is. The Anti-lock Braking System is a crucial safety feature that prevents your wheels from locking up during hard braking or when you are driving on slippery surfaces. If you have ever had to slam on the brakes to avoid a deer near the Bu ... read more

The Silent Killer of Your Engine: Recognizing a Failing Fuel Pump Here in O'Fallon, we know that life moves fast. Between the commute down Highway K and the weekend errands around town, we often take for granted the complex machinery that gets us from point A to point B. At Hillside Auto Repair, we see it all the time: a vehicle that starts to feel a little "off," and the driver chalks it up to bad gas or the weather. But more often than not, that sluggish feeling is the first whisper of a failing fuel pump. Understanding what this component does and how to spot its death rattle is the key to avoiding a sudden and inconvenient breakdown on the streets of O'Fallon. So, what exactly does this mysterious part do? Simply put, the fuel pump is the heart of your vehicle's fuel system. Usually located inside the gas tank, its primary job is to draw gasoline out of the tank and push it through the fuel lines to the engine. It isn't ... read more