How much does a replacement or reprogrammed ‘plug and play’ ECU / ECM cost?

Note: A high quality vin matched replacement ECU / ECU is typically $600 less than dealer installed parts.

How to Test for ECM Errors and Problems

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Testing your ECM is the only way to be sure whether it’s not working properly, or if there is a different component causing an issue with your car.

Do you need a replacement ECM for your vehicle?  We carry engine control units (ECUs) for all makes and models.  

We all dread this day. We’re driving to work or going about our normal daily routine, and just like that we notice a problem with our car. If we’re lucky, it’s nothing serious and we can keep driving and carry on with our day. But we still know in the back of our head that eventually we are going to have to get the car fixed. And if you know about ECMs (engine control modules), then you know that that’s an engine component that you definitely don’t want to have problems with.

If you’ve read previous article of ours then you understand how important the ECM is to a well-functioning, healthy vehicle. Through a system of sensors and circuits it monitors, regulates, and controls nearly every part of your car’s engine. Because it interacts with so many other vehicle systems and processes, it can potentially cause wider damage to your engine if it is malfunctioning and isn’t taken care of quickly.

There are certain symptoms and signs that may indicate you have a failing engine control module, but the only way to know for sure is to test your ECM for errors and issues when problems arise.

Signs Your ECM Needs to Be Tested

Because the ECM plays such a crucial role in modern vehicles, there are some serious symptoms that can occur if it is not working properly.

  • Check Engine Light – A lot of people see the check engine light and think it’s probably nothing or that it is something we don’t have to worry about right now. For some people, it is always on and they are just used to it. But this is exactly when you need to look at your engine most! If the light is constantly on and is not going off, or there doesn’t appear to be any reason for it to be on, it could be a sign that your ECM is faulty and it is definitely worth it to get it checked out.
  • Engine Stalling or Misfiring – A bad or malfunctioning engine control module can also cause erratic and unpredictable engine stalling or misfiring. This is because the ECM controls the fuel pump, fuel injector, spark plugs, and transmission—all the parts you need working correctly for your engine to run smoothly. The stalling or misfiring is a result of fuel and timing issues due to the engine not getting information properly and its systems not working together correctly.
  • Reduced Power – If you notice that your car has reduced power or slower acceleration, this could also be the result of a failing ECM. Again, the engine control module is what allows the pedal you are pressing down to communicate with all the necessary components to give you the power you need.
  • Car Doesn’t Start – Another troublesome sign of a bad ECM is your engine having problems starting or not starting at all. This could be caused by other things like a shoddy alternator or bad battery, but could also be the result of issues with the ECM preventing the engine from getting the vital information from the car’s computer it needs to start.
  • Reduced Fuel Economy – If you normally pay attention to your fuel economy and notice it getting worse and you aren’t sure why, it could also be a sign of a broken or malfunctioning ECM.
  • Gear Shifting Issues – When the ECM is faulty or failing, it will throw off the timing of fuel settings of the engine and could result in your vehicle struggling to change gears or not being able to shift at all.

How Do I Test My ECM?

Again, it’s important to note that the above signs and symptoms can be the result of other system failures or problems with your vehicle. Running diagnostics and testing your ECM is how you can rule out other issues and see if there is really something wrong with the engine control module itself.

The first thing to do is test the ECM to see if it returns any error codes indicating a failure of a specific engine system. For example, if you are experiencing misfiring, then a diagnostics test of the ECM should return an error code showing a problem with one of the cylinders. And from there you can determine if the cause is worn out spark plugs, spark plug wires, a faulty ignition coil, etc.

If, however, you’re pretty sure the problem is with the engine control module itself, there are several types of tests you can run to find out.

First is the functionality test, where the ECM tests whether all the components in the engine are producing the desired changed or the changes that are being expected. Then there are rationality tests, in which the sensors are tested to see if they are providing information in perfect balance. This kind of test ensures that the sensors and the information provided by each of them do not contradict them. Lastly, there’s the most basic test, the circuit interesting test. This will ensure that all the components are functioning and all the wiring is perfect.

Can I Test My ECM at Home?

The problem with testing an ECM yourself is that it requires specialized knowledge, tools, and software. If you don’t know where to begin, and aren’t sure how to create and carry out the types of tests listed above, it is probably best to leave it to a trained technician or mechanic. They’ll have the proper tools to run all the necessary tests on your car computer and let you know what the root of the problem is.

If, after testing, it comes back that the problem is in fact a faulty ECM, then your best bet is to replace it as soon as possible.  At Car Computer Exchange, we’ll send you a newly programmed and tested ECM suited to your exact vehicle. And installation is so simple that that definitely is something you will be able to do on your own!