Lately my car has decided to build less boost and I can't seem to find the problem. It was spiking 20 and holding 18, but now it spikes at about 16 and holds 14-15. Checked all the hoses and everything looks good, and my fuel trims are -0.9% idle and 7% mult.. I'm gonna log my timing, AF ratio, and actual vs. specified boost either Friday or Saturday but I wanted to see if you guys know anything else I should look at.

mods: apr 93oct. tune , fmic, 3in. dp, milltek exhaust, tip, intake

MAF and O2 sensors have less than 5000 miles on them.

Thanks for the help.

 

exhaust leak ? could be the dp

any CEL. ?

 

No CEL, and I didn't think an exhaust leak could cause a loss in boost but I'll check it anyway just to make sure.