Most of my problems have been boost problems.. My timing was off 4 degrees.. My engine has low compression in cylinder 4 and 6 (6 not so bad).. I had 10 boost leaks at one point.. My 2nd turbo is gone.. but has made no death whine.. no smoke.. and no grinding.. I have had numerous coolant leaks.. My turbo timer was wired wrong.... it goes on and on..