Where is the ECM located

Good afternoon,

It is located on the firewall on the passenger side under the hood. I attached a picture for you to view.

Who told you it needs to be replaced? What were or are the codes that were set?

https://www.2carpros.com/articles/engine-misfires-or-runs-rough

Roy

Rough running and idle sounds more like a fuel or ignition issue. Is this a flex fuel engine?The ECM isn't a likely suspect for those, especially with it being a 3.0 which have a few issues as they age. When was the last time the plugs were changed? Any codes or lights on? Have you done any other testing? Also you cannot just swap out the ECM on that vehicle without having a dealer level scan tool to reset the unit and program it to match your VIN.
As for it's location it's mounted in the cowl on the right side above the heater hoses. The connector is easily seen but the ECM itself is hidden.

Okay, it is not under the dash. It is outside the car under the hood as both myself and Stsve have told you.

Before you replace it, did you do a compression test? Does it have any codes?

I would not be too quick to pull the trigger on an ECM before you are sure the engine is in good condition.

Roy

Run a fuel pressure test on it, running lean and rough are both common signs of low fuel pressure. Yours uses a fuel pump driver module that pulses the pump on/off to control the pressure. You want to see 35-70 psi. The easiest way to test them is with a scan tool with bi-directional control and using a mechanical gauge as well as the pressure PID the scan tool reads. That gives you a way to verify the pump and the pressure sensor are reading the same. The control unit is behind the right hand C pillar.

Let us know what you find. They can be a handful because of the design. Guess someone thought it was a better design than a simple regulator.