I had the exact same problem! After i got my head repaired i could have swore I saw 1.3-1.4 regularly then after fix 1.1-1.2. Mine acts just as ur describing and I have no issues anywhere and after alot to research the car is acting normally and feels like it pulls the same as it used to. I also noticed my boost guage when off sits a little low not 100% on 0 so i add that in as a factor. But under 1.0 bar doesnt seem right, i've never seen the car boost under that.

 

I don't boost lower than 1.0 it just doesn't go over.

 

UPDATE:

I installed my new autometer boost gauge, now I'm concerned why I'm boosting 24psi at WOT, my car is stock, btw my stock gauge still reads only 1.1 bar.

Oh, and I teed into the fuel pressure regulator line.

Secondly when I'm boosting i hear a hissing noise from the boost gauge (the new one) I'm wondering if I installed the line into the gauge right, I put a copper bead on the line then screwed the tap on the gauge

 

Bump

 

My MR boosted to around 19-20 and then tappered down to about 16-17 by redline. Usually would hold better in higher gears.

Boost levels can obviously change depending on elevation/temperature. I'd say you have a small leak somewhere.

 

1 bar is only about 14.5 psi. When my Evo IX was stock it would hit about 21 psi and then taper down toward redline. That equals about 1.45 bar, which is around what I think you should see.

 

the problem you might have are the cats in the downpipe getting clogged, open them up or use an aftermarket downpipe.. btw same situation here 0.8 bars stock evo IX..

 

Buy a MBC and it will fix your boost levels going from 21ish to 17. That was one of the first things I bought after my DP and exhaust. But if your at 1 bar or 14.5psi then it sound like theres a leak somewhere. Try doing a boost leak test.

 

check your throttle body shaft seals..its that 90% of the time

 

You should be reading about 1.3 bars on all other gears except first gear. Do a boost leak test first to determine what is going on.

Carlos