So I just purchased a 2007 Expedition that had some engine problems. I am fairly decent and fixing and diagnosing engine problems so I decided to purchase this vehicle and take on the challenge. However I am running into 2 things.

First off the vehicle had problems idling and driving. After removing the head from the vehicle I discovered that one of the valve springs was completely broken. I replaced all the valve springs and valves. Now after putting everything back together I am running into 2 problems.

First off the ABS/Brake light is on. I pulled the codes and found code U0121 Lost Communication With Electronic Brake Control Module

This code was not there before removing the heads from the vehicle so I suspect I forgot to hook something back up. I didn't mess with the EBCM so I suspect a ground issue. Can someone please help me identify the location of the ground point for the EBCM.


Second problem - The vehicle is shuttering/hesitating/jerking at low rpm acceleration. There is no CEL for this problem. I am certain that I did the timing correctly and that there are no vacuum leaks. I need some more thought on what this could be.

I ordered some new coils and a fuel filter to rule these out but they will not be here for a few more days.

 

Changed the coils and still same problem.

I also discovered this strange noise when its put into Drive. There is no noise when in park. The noise seems to be coming from the drivers side area. Any ideas?

 

Which head did you pull?
Sounds like a possible exhaust leak either from the exhaust manifold or where it is bolted to the head. You might use a piece of hose to pin down the exact area where you place the hose close to your ear and the other end search around to see where the noise is loudest. Also if you remove anything removable from that side valve cover you can confirm if it is coming from under that valve cover .