[JFP in PA]

That narrows the field; this code has multiple definitions, depending upon the DME version. With the 7.2 DME, you have a throttle body issue; the “springs” issue that Mike noted (this is housed in the side of the body itself). This can be caused by build up on the throttle plate itself, or the electronic sensor unit on the body. As yours is a new unit, I would think that build up is not an issue. Now the tricky part; if memory serves, there was an upgraded replacement throttle body released that required a “re-flash” of the DME to work correctly, this may be your issue.

When a new body is installed, you should run a short procedure to “set” the throttle motor; disconnect the battery for a moment, reconnect it. Turn the key to "on" but do not start or touch the gas pedal - wait 1 minute (you should hear a small motor on the throttle body engage and then reset) - turn the key to off and remove the key for a moment or two. Then reinsert the key and start the car, it should rev normally now. If it does not, you may need the re-flash. If that is the case, you may want to give your dealer a call with the new body’s part number and your VIN; they should be able to tell you if you are in the market for a re-flash.