I am having the same problem as this post from 2010. It is driving me in to the ground and I can't find if anyone found a aolution. Please help" Hey, Im new to mack and this forum so bare with me. I recently picked up a 2006 chn613 with a e-7 427 in it. The truck has lost power problem for the past 2 years. Ok,so the boost comes up incredibly slow,(sometimes only build boost once I hit 5th gear) the boost squeals rather than has the normal high pitch clean wistle. The boost sound fluctuates up and down along with the boost gauge (back and forth from 32lbs-25lbs) rapidly. Sometime the boost will spike and hold 40lbs but makes no real power. I dont know what to do and I have alot of trouble trying to explain the problem. Has a new egr,new intercooler,new cooler plumbing,some new boost sensor (? on the driver side firewall?)injector pumps, I get alot of codes popping on the truck but none of them pan out most often is 3-4(forgot what that was) but was told by the mech that there is NO ISSUES AT ALL with the truck. Does anyone have any idea of what this could be or what I could do to check for any intake leaks or if the turbo is bad? Ill spend the money to fix it one last time, and after that if I get nothing out of it Ill have to close shop and go back to being a company man if im lucky. Please help!!!! Thanks so much for your time!!!!"
