Idles fine, no power and shuts off when driving

My buddys car had to be towed back as it started stumbling and had no power. We replaced the EGR and the IAC and it idles and revs just fine in park but the moment you put it in drive it loses all power and starts stumbling and is incapable of being driven. I'm at a loss.

Oh, and the brakes are almost non existent and shuts off when trying to drive and the EGR is getting extremely hot