low boost

[racerfreak]

anybody have any ideas what could cause low boost other than a leak . i replaced all the boots and did a pressure test and found no leaks but my boost will not go over 20 lbs but also i am not getting any smoke but before i lost my boost i had a lot of smoke on take off

 

[ChuMaDD]

When was the last time you looked at your air filter? And you should tune your truck properly to not have a lot of smoke on take off....

 

[Tate]

Torn AFC diaphragm?

 

[racerfreak]

diaphram is good the only thing i can see is something is happening in the fuel system my press. is 52 lbs

 

[Hurley]

afc reference line unhooked?

 

[kino_fab]

^^^ or the hard line that runs from the AFC to the waste gate has a hole rubbed into it around the exh. manifold if you are still using it.