MIL a.k.a check engine light

September 2, 2024

Most people look at the MIL or the dreaded “check engine light” as a sign of evil. They call out to the God with phrases like “not you again” or “oh $#!+” following shortly after. The truth is that the MIL (malfunction indicator lamp) is actually a friend with a case of mistaken identity. As the name suggests, it is a lamp in the instrument cluster (gauge cluster) designed to come on when the extremely smart and sophisticated ECM (engine control module; computer) realizes that there is a system in the vehicle that is not functioning the way it is supposed to and may cause damage to crucial engine components.

The ECM looks at every aspect of the engine’s performance and makes very fine tuned adjustments to keep the engine running at its best. But, when one of the sensors gives a faulty reading, the ECM tries to compensate for it for as long as it can, before throwing on the MIL. While this is the normal way for the ECM to react to the faulty readings, it may in some cases cause the engine to perform very poorly and may even prevent you from driving the vehicle safely. For example, you may not be able to accelerate, you may not be able to go over a certain speed or the vehicle may idle very rough. If left unattended, a fault code in the ECM may lead to expensive repairs and unnecessary parts replacement that could have been avoided.

The purpose of the MIL is to caution you about the possibility of poor emissions from the vehicle due to a sensor or system malfunction. Now we all want to keep mother earth as clean and fresh as possible and want to help in any way we can, so ignoring an illuminated MIL would be doing the exact opposite. When the MIL is illuminated, your vehicle is not running at its optimal. Your fuel consumption could increase many folds causing excessive unburnt hydrocarbons (nasty black exhaust residue made of hydrogen, oxygen and carbon) to exit the tail pipe of the vehicle and be released into the atmosphere. Elevated levels of NO, CO, CO2 and other harmful and toxic gases also escape the tail pipe roaming freely in the atmosphere, which are responsible for increasing the greenhouse effect of the planet (global warming) and depletion of the ozone layer, which is our only defense against the extremely dangerous UV rays of the sun.

So, ignoring the MIL has so far caused you to use more fossil fuel which powers the engine, your wallet has gotten lighter rather quickly and also caused some amount of damage to the atmosphere. Now it may not seem like your 1 car can do much damage, but what if there are others who have left their MIL unscanned and unrepaired. Let’s put this in perspective, shall we. In the year 2005, there were a total of 17.9 million light vehicles registered in The Great North as per Natural resources Canada. If only 1% of those vehicles had their MIL’s illuminated for one or more reasons, that’s 170,000 light vehicles not running as efficiently as they should, burning more fuel than they need to and causing excessive pollution in our country. How about another simple calculation? From my personal experience, my 2002 Chrysler 300M would only go 400 kms per tank when the MIL was illuminated as opposed to 500 kms when it was running smoothly. If my fuel tank took 60 L of fuel, it gives me a consumption of 12 L/100 kms when my car was running fine, but when it wasn’t; I was using an extra 3 L of fuel to go the same distance. Hmm, doesn’t seem like much. But let’s include the other 1% drivers like me and assume they all used the same 3 L of extra fuel on an average. Combined together, we wasted 510,000 L of gasoline. That’s 8,500 gas tank fill ups with a capacity of 60 L wasted, or 4.2 million kms of driving distance that I couldn’t go in my Chrysler.

If the trend continued and more and more people started ignoring their MILs, how long would it take for us to tip the delicate balance of our atmosphere? Frankly, I do not have an answer for that, and neither do I want to know because sometimes ignorance is bliss. But at least I know I’m doing my part by keeping my vehicles running at their very best and tackling the issue that cause the MIL to show up.

There are multiple reasons for the MIL to illuminate, loose gas cap, faulty oxygen sensor, one or more cylinder misfiring are among the most common. Although, in most cases it would be ok for you to drive your vehicle to the repair center and get diagnostic performed on the vehicle to find out the cause of MIL, in case of a misfire when you have a flashing MIL, the vehicle should not be driven and the engine should be turned off as soon as it is safe to do so. Continuing to drive the vehicle when the MIL is flashing is an indication that one or more cylinders are not able to combust gasoline in the engine and as a result unburnt gasoline has been sent to the exhaust pipe. But before it goes out the exhaust tip, it’ll have to pass through the catalytic converter which can be as hot as 500 degree Celsius and will burn the gasoline instantly, something it is not designed to do, as this leads to the catalytic converter getting even hotter and melting its honeycomb arrangement of precious metal into a lump and rendering itself useless causing the vehicle to run poorly, burning more fuel and not be able to take care of the toxic exhaust fumes. This will in turn cause you to dish out lots of dollars to get the cats replaced. So once again, acknowledging and repairing the cause of the MIL can save money and the environment.

So, essentially the MIL is designed to save you money while saving the environment at the same time. But, how do you know what the MIL is trying to tell you. There’s a whole bunch of small scale ECM scanners that could look up the code and give you a description, and that’s it. These small scanners cannot perform much of the diagnostics and even viewing live data from the ECM is usually very slow to be of any use. A proper scanner can tell you the code, a description of it and will be able to perform active tests to see what part needs to be replaced. These scanners can also check other systems of the vehicle and perform testing on those as well for example SRS, ABS, Hybrid systems, etc. But, they come at high costs and are not a reasonable purchase for the common household. So, if you have an illuminated MIL and want to get it checked out, visit us at Mecano Autoworks Inc. and we’ll gladly hook up our scan tool to tell you what the ECM is trying to tell you.

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Laser Rust Cleaning for Automobiles: A Game-Changer for Toronto's Harsh Weather

By Rish Bhatia • April 29, 2025

Introduction Toronto, Ontario, is known for its beautiful, diverse seasons, but with these come some of the most challenging weather conditions for automobile owners. From the harsh, salt-laden winters to the humid, rainy summers, cars in Toronto and surrounding areas face a relentless battle against rust. Traditional methods of rust removal can be tedious, costly, and often temporary solutions. Enter laser rust cleaning—a revolutionary technology that promises long-term benefits for automotive maintenance in adverse weather conditions. Understanding Laser Rust Cleaning Laser rust cleaning, or laser rust removal, is a process that uses high-powered laser beams to remove rust and other contaminants from metal surfaces. This method offers a non-contact, non-abrasive solution, making it highly efficient and precise. The technology works by directing a focused laser beam onto the rusted area, causing the rust to vaporize through rapid heating. This leaves the underlying metal intact and clean. How It Works The process involves the following steps: • Preparation: The vehicle is prepared, and the areas affected by rust are identified. • Laser Application: A laser cleaning machine is used to direct the laser beams precisely onto the rusted surfaces. • Rust Removal: The laser energy causes the rust to heat up and vaporize, effectively removing it without damaging the metal underneath. • Final Inspection: The treated areas are inspected to ensure all rust has been removed and the surface is smooth. Advantages of Laser Rust Cleaning Laser rust cleaning offers numerous benefits over traditional methods such as sandblasting or chemical treatments. Here are some key advantages: 1. Precision and Efficiency Laser rust cleaning is highly precise, allowing for the targeted removal of rust without affecting surrounding areas. This precision reduces the risk of damage to the car's body and ensures that only the rusted portions are treated. The efficiency of the process also means that it can be completed in a shorter timeframe compared to traditional methods. 2. Environmentally Friendly Unlike chemical rust removers, which can release harmful substances into the environment, laser rust cleaning is a clean, eco-friendly process. It does not involve the use of any chemicals or abrasives, reducing the environmental footprint. 3. Cost-Effective in the Long Run While the initial investment in laser rust cleaning may be higher than traditional methods, the long-term benefits make it cost-effective. The process provides a more permanent solution to rust problems, reducing the need for frequent treatments and repairs. This longevity translates to savings for vehicle owners over time. 4. Non-Invasive and Safe Because it is a non-contact method, laser rust cleaning does not cause abrasion or wear on the metal surface. This characteristic makes it a safer option for delicate parts of the vehicle. Additionally, it minimizes the risk of health hazards for technicians, as it does not produce harmful dust or fumes. Long-Term Benefits in Adverse Weather Conditions Toronto's weather conditions can be particularly harsh on automobiles, making rust prevention and treatment crucial for vehicle longevity. Here's how laser rust cleaning proves beneficial in such environments: 1. Durability Against Salt and Moisture During Toronto's winter months, roads are often treated with salt to prevent ice formation. While effective for road safety, this salt is highly corrosive to vehicle metal surfaces. Laser rust cleaning provides a thorough removal of rust and a clean surface that can be effectively treated with protective coatings, enhancing durability against salt and moisture. 2. Enhanced Protection from Humidity Summers in Toronto can be humid, leading to increased moisture levels that contribute to rust formation. By removing all traces of rust and properly treating the cleaned areas, laser rust cleaning helps in protecting the vehicle's metal surfaces from the adverse effects of humidity. 3. Improved Structural Integrity Rust can significantly weaken the structural integrity of a vehicle over time. By eliminating rust at its root, laser rust cleaning helps maintain the strength and reliability of the car's body, ensuring it remains safe and roadworthy. 4. Aesthetic Appeal In addition to its functional benefits, laser rust cleaning also enhances the aesthetic appeal of a vehicle. Rust can be an eyesore, detracting from the overall appearance of the car. With laser rust cleaning, cars can be restored to their original, pristine condition, which is particularly beneficial for collectors and enthusiasts who take pride in their vehicle's appearance. Conclusion Laser rust cleaning represents a significant advancement in automotive maintenance, offering a superior alternative to traditional rust removal methods. Its precision, efficiency, environmental benefits, and long-term cost-effectiveness make it an ideal solution for car owners in Toronto and other regions with adverse weather conditions. By investing in laser rust cleaning, vehicle owners can ensure their cars remain in optimal condition, withstand harsh weather, and enjoy a longer lifespan. As technology continues to evolve, it is likely that laser rust cleaning will become a standard practice in the automotive industry, setting new benchmarks for maintenance and care.