Humming sound from engine when making boost
 

Recently replaced up pipes, took truck for a test drive and everything sounded great, except for now when the turbo starts making boost I hear loud humming noise coming from under the hood?? Also the turbo makes a swoosh sound when I let of the pedal?? Neither of these noises were noticable before, just curious what I should be looking for? Normal driving everything is good, only notice it when I get on the throttle, almost sounds like when you blow air across a bottle???? Any help greatly appreciated, thanks.:argh:

You have a boost or exhaust leak somewhere.

Check all the boots from the intercooler to the turbo. There are a total of 6 boots there with 12 clamps.

It could also be the babys butt behind the turbo that is not seated properly causing a drive pressure leak there.

Humming sound from engine when making boost
 

What is normal psi off the map sensor? Cuz I think mine makes same sound but not sure

Yup thats exactly what it was, boots at bottom of spider pipe were just slightly loose from the install, thanks for the intel. Hey where can you get those gauges you show on your avatar???

Those are Isspro gauges.