idm grounding problem

[davidschaffer]

So with the idm unbolted from the side wall the truck runs great, but there is current on the outside of the idm box, when the idm is bolted to the side wall ( grounded ), the truck only runs on 4 cylenders. Any ideas? Help soon would be much appreciated.

[alberta 7.3]

If the truck runs fine without the IDM touching the body, it is probable that the IDM has an internal short to the case. If you had a spare IDM to test with would be the best bet.