Have someone check it for codes. Chances are it's in limp mode.

 

And what is "limp" mode?

 

Reduced power.

Have you checked for codes?

 

There's nothing to indicate a trouble code is present (i.e. Check Engine Light). Can she have a trouble code without the Check Engine Light or another indication?

 

Codes will store in the ECM. Usually if a code trips the CEL, if it auto fixes itself, the CEL will go out, but the code will still be in the ECM.

 

How can I and should I reset the ECM? My brother said there is a procedure for resetting the ECM. Something about disconecting the batteries and turning the key on and off a number of times. Is this how it's done?

 

Yes, you need to hook up a code scanner. The "chekc engine" light doesnt necessarily have to be on for there to be code present. You should invest in a code reader, or a Smarty.

 

I think there is some confusion here. I would try doing this:

1. Set parking brake
2. Disconnect negative battery cables on both batteries
3. Turn ignition key to run(to drain any remaining capacitors)
4. Let truck sit for 30 minutes( this is the recommended minimum)
5. Return ignition to OFF position
6. Reconnect both batteries and secure, this is not a timed event

 

Does this have a 6.7 or 5.9? I have worked on plenty of 5.9 trucks and have not run across this with an intake swap, but the Ford 6.0 L had this problem a lot with aftermarket intakes and the ECM not recognizing the MAF Sensor signal with the increased airflow. Probably the only fix is to put your stock intake back on and live with it.

 

updates???