I have an 86 F250 with a 6.9 and i recently had the gas tank replaced. As soon as i went to pick it up from the mechanic and cold started it there was a tremendous amount of blue smoke coming from the exhaust. Before the repair i had maybe a puff or two upon a cold start but other than that no blue smoke whatsoever. Anyways, it blue smokes on startup and all the way until its warmed up. From that point when your under acceleration it will randomly puff small amounts of blue smoke but the second you let off the throttle a large puff of blue smoke comes out. Before the gas tank was replaced i could board the throttle and roll a little coal (pump is not turned up and everything is stock). But now when i board it the exhaust appears to be clean?? Other problems that happened at the same time is a minor loss of power, rough idle, and almost chugs when you get into high rpm (when going from 2nd to 3rd in a 3 speed auto with 4.10 gears). One other thing i might as well mention is that the truck goes through about 3 quarts of oil every 700 miles or so with a very small amount of it leaking but i never get an oil smell coming from the exhaust. The blue smoke definitely has a raw fuel smell to it though...Im wondering what could cause this issue? Air in the fuel lines or plugged injectors?? Im a new diesel owner and want to make sure nothing is getting destroyed. Thanks in advance!

Chris

 

maybe a air bubbles in your fuel line from the tank swap you could put a diesel grade clear line from filter to ip pump to check it