I have a 2004 CX613 with a E7 427. When the truck runs right it has great power on low and top end. The truck occasionally loses power. The turbo sounds like it is not spooling up. When it loses power the exhaust gets loud as though the muffler was taken off going down the road. Loud on acceleration and slowing down with the Jake on. The electrical malfunction light only comes on some times. Have not been able to read any codes because the malfunction light does not stay on. Engine also idles rough. Almost appears that it loses a cylinder. Any help would be great. Please advise.
