Slideshow: How Optimized ECU Programming Enhances an Engine

You can get more out of what you've got.

You wouldn't hack a computer database. You wouldn't hack an ATM machine. However, in a certain sense, you can hack your car. As an experienced car tuner might tell you, this can leave your ride in better shape than before. Of course, this comes with the assumption that your car is modern enough to come with a programmed ECU-- an engine control unit for those unaware.

There's also the warning that the risk of improper programming can practically turn your engine into scrap in the hopes of what is a relatively minor boost in performance. Then again, the potential cost to gain ratio is probably why many owners never think to tweak the way their engine thinks. There are a lot of competitive scenarios where wringing out that last little bit of power can mean everything. Beyond that, some modders still won't rest until they know their car is as refined as it possibly could be. By tweaking the operation of your engine to match modded parts or specialize for a desired performance, an optimized engine can conceivably operate better in every way when properly programmed.

An orchestra's only as good as its conductor. 

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A quick rundown: ECU 101.

The advent of electronic ignition systems allowed for engines to be controlled with a pinpoint degree of precision. No matter the mass or make of an engine, it'll only perform as well as it's told to. An ECU's programming dictates virtually every quantifiable aspect of the engine's function; not limited to things like RPM, fuel delivery, spark timing, and air temperature. Inputting values for these different facets can be as simple as plugging them into a spreadsheet, then uploading the new program through the car's OBD-II port. It's figuring out each value and balancing them against all others that give reprogramming a high skill floor. 

It's worthy to mention that your car may have a powertrain control module (PCM) in lieu of the engine control unit. This fills the same purpose for the engine as the ECU, with the benefit of being integrated with control of the transmission as well. This combination allows for optimal synchronicity between the parts.

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Default programming appeals to the lowest common denominator.

Something might come as a surprise to you; engine control units are intentionally programmed to be suboptimal by the manufacturer. A vehicle fresh off the lot could be running a little better, but manufacturers will typically program an ECU to give significant lenience for owner error. For instance, a car running at its best might also become more susceptible to breakdowns if it wasn't seeing the recommended level of maintenance. The automakers cater to the lowest common denominator in part to avoid a bad reputation as a "shop magnet." Most owners looking into optimizing an ECU aren't like the common driver; there's untapped potential there basically waiting to get programmed to life.

>>Join the conversation about Optimizing ECU Programming for Peak Performance right here.

Disastrous consequences for the ill-prepared.

Be advised that custom ECU optimizing is something that requires a high level of know-how to do properly. If you're doing it for the sake of a performance build, you should hire a specialist. All kid gloves and padding come off when you're messing with the program directly.When things like fuel injection and spark timing are concerned... well, you can imagine how many ways something could go wrong.

There's also the issue of a car's warranty and insurance. Given the risks inherent in reprogramming an ECU, it's recommended you check both first to see how they'll be affected by the tuning. A car's programming can simply be reset with a manufacturer ROM as well. While most helpful if you foul up with the code, some people reset their car on a seasonal basis, reporting that their car works better as a result.

>>Join the conversation about Optimizing ECU Programming for Peak Performance right here.

...speaking of disastrous consequences.

If you want a specific example where ECU programming has had grave consequences, we can do you one better than mere engine problems. Looking for disastrous consequences? Look no further than your friends at Volkswagen.

Chances are you've heard of the 2016 emissions scandal, a multi-billion dollar fiasco for Volkswagen. It's arguably best looked at as a how-to guide on destroying your company's reputation, but fortunately for us, it's had the result of making ECU programming relevant and topical. Without getting into it too much, the Volkswagen Group tried to cheat the government emissions tests with sophisticated ECU programming that would run the cars much leaner than they would on the road. This use of a "defeat device" helped mask the fact some of their cars were spouting out nitrogen oxide in heaps as much as 40 times the United States' legal limit.

>>Join the conversation about Optimizing ECU Programming for Peak Performance right here.

There's untapped potential in every engine.

Other automakers have since been investigated for use of defeat devices. Despite the headache, it's caused the Volkswagen Group, it was their dishonesty-- not ECU programming itself-- that made their mess. When the code's optimized properly, you can reasonably expect some improved performance out of it. Just provided you're smarter about it than they were.

Which shouldn't be difficult at all.

>>Join the conversation about Optimizing ECU Programming for Peak Performance right here.

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