Failing Engine Control Module: Your Guide to ECM Problems

The engine control unit or engine control module is the main computer for most modern vehicles. This crucial component controls many of the engine performance and drivability functions. It derives information from the engine’s sensors and can use that information to tune engine spark and fuel for efficiency. When something happens to your ECM, it can impact a variety of your vehicle’s functions. In some instances, it may even leave your car completely undriveable.

If you aren’t a mechanic, you may feel lost when you have vehicle trouble. How do you know what’s wrong with it? How do you know if it’s something that warrants a trip to the mechanic? If your ECM is having trouble, it can be extremely serious. Here is what you need to look for when it comes to a damaged ECM. In addition, find out what to do if you suspect that there is something wrong with your vehicle’s computer.

What Are Symptoms of a Failing ECM?

Engine Stalls

Whenever your engine begins to act erratically, you should be concerned. Engine stalling may manifest as failing to start at first or your engine may even fail while driving. There are several different reasons that your engine might stall. It could be dirty fluid, overheating and more. Often, it is also due to the ECM.

Car Fails to Start

Imagine that you wake up in the morning and get ready for work only to find out that your car won’t start. It started fine the day before, but suddenly it fails to start. Perhaps you ignored some of the more common signals. For instance, the check engine light may have been turning on but you thought little of it. Keep in mind that this light usually illuminates if the computer detects a problem with the circuits or sensors. It is true that there may not be an issue, but you always want to check. Whatever the case, your car won’t start. When the engine won’t start, it could be a problem with the ECM. Your engine may still crank, but it won’t start because it doesn’t have the correct inputs from the computer.

Fuel Economy Changes

If you drive your vehicle on a regular basis, then you already know roughly how much fuel it burns on a daily basis. If the engine control unit ECU or powertrain control module malfunctions, then you may see a sudden change in fuel economy. Your engine cannot determine the right quantity of fuel to burn when its computer is malfunctioning. Due to this, you may burn through gas quicker and hence spend more money on fuel than you did previously.

How Can You Test if Your ECM Is Failing?

If you start to witness any of the above symptoms with your vehicle, then you need to find out for sure if it is your ECM. First and foremost, you can run diagnostics to find out how your ECM is performing. You can rule out different issues through testing. Your first move should be to test the computer. The error code can tell you what the problem is and then you can determine why the issue is occurring.

Now, the major question that you probably have is whether you can perform the tests on your own. The two popular tests are the functionality test and the rationality test. The functionality test checks whether the components in the engine are producing expected changes. The rationality test is to ensure that there are no contradictions between the sensors and the information provided by them.

If you want to perform the tests on your own, you may be disappointed. Without the knowledge, software or the tools, you won’t be able to perform the tests. It is always better to go to a trained mechanic to have the tests performed. The mechanic will be able to tell you if the problem is with the engine control module ECM.

Should You Replace or Repair Your ECM?

When your ECM is failing, you probably just want your car to run again. It doesn’t necessarily matter what it takes, as long as you have a vehicle that runs. Of course, budget matters. After all, you don’t want to spend more money on repairs than the vehicle is worth. The older the vehicle, the more likely you are to run into that problem. So, how do you know what to do with your vehicle? Most of the time, when an ECM goes bad, the best solution is to replace it. The engine control modules aren’t designed for repairs. Not to mention, it is a lot easier to replace th ECM than it is to repair it. After all, swapping out the old one for a new one can be completed by most mechanics. It takes someone with specialized knowledge and tools to be able to make repairs.

In order to make repairs, the mechanic will have to disassemble the entire unit. Then, he or she will have to perform extremely precise electrical work. For example, think about the motherboard of a computer and how complex it is. Most people cannot repair it on their own. In fact, when your motherboard is damaged, most would say that you have to replace it or the computer itself. This is the same concept.

Mechanics may open up the unit and look for any signs of electrical damage. Then, they will look for corrosion. Once they find the evidence of a problem, they can figure out how to fix it. However, just because a mechanic sees no visible signs doesn’t mean that there isn’t a problem.

When it comes to the engine control module, you need it to be functioning in order for your vehicle to perform properly. If it’s in need of repairs or a replacement, then your vehicle may stop working entirely. Most mechanics have the tools necessary to diagnose any issues with your vehicle, particularly with the ECM. Whether you see a drop in engine performance, an overconsumption of fuel or a stalling engine, it could all be a sign that the computer suffered damage.