I have an 2007 5.9 and its been pretty much problems since I got it but right now its is acting wierd it runs just fine for about 30 mins to an hr. When it warms up it starts to miss and puff black smoke. It misses at about 2500 rpm when your really hammering it but if u drive it sorta easy it doesnt miss as bad it almost ask like a gasoline that has a fowled spark plug or one that is starting to go bad. any help or ideas would be good bc im clueless and about to take it to the shop.

 

When did you last change the fuel fiter? I would start there just in case you got some bad fuel. Second what is your fuel pressure? Enough to keep the CP3 supplied? Next have you seen the articlke about teh chafed wire, might be another place to look. From there might be a plugged injector, how is your oil level? If growing oil probably a bad injector. How about your air filter, changed it recently? Boost boots still connected OK. Running out of ideas but at least a start.

 

chafed wire? dont have a fuel pressure gauge so would have to look into that uh oil level is low there is about 2 quarts a day going somewhere.

 

chafed wire? dont have a fuel pressure gauge so would have to look into that uh oil level is low there is about 2 quarts a day going somewhere.