A couple days ago, for no reason that i can tell, my CTSC started losing boost. Everything seems fine until about 7K, then my boost just levels off. There's a noticable loss of acceleration as well.

I've checked my belt and it's plenty tight. The only thing I can think of is my bov could be leaking. Anybody have any thoughts?

 

Check your vacuum lines.

 

check ur ic pipings u might have leak there

 

1. Check your transition hose from the the throttle body to the Aftercooler (if you have one)
2. Check your transition hose from the blower to the aftercooler (if you have one)
3. Check your air filter. You'd be surprised....give a good cleaning you you will feel the difference!!

 

I have the same problem too.. but lately i am logging late at night which might be humidity issues.

I run on a 7psi pulley

 

I don't think mine has anything to do w/ humity. I was doing a few pulls late at night to fine tune my a/f a bit, and it started doing this between one pull and the next.

So last night:

I inspected all my major transiations; replaced a suspect clamp.

Inspected all vacume lines; replaced the check valve.

Removed and inspected the BOV; relubed all o-rings and reinstalled.

Still having the same issue. The BOV seems to be working fine, but it's still my primary suspect b/c i can't think of any other areas I could be losing boost from. Tonight I will remove it and replace w/ the stock ct "bov" and see it that could be the issue. I can't hear the BOV releasing air when my boost levels off, but my exhaust is very loud at that point so it's possible

If it's not the BOV, I have no idea what it could be.

 

In case anyone runs into the same problem, i figured out what this was. I had a bad MAP sensor. I was reading boost from the MAP so it looked like a boost leak, and b/c of the effect of the ecm, it felt like a boost leak.

Replaced the MAP and boost is reading like it should, but will need to redo my tune.

 

This afternoon the weather was perfect and logged my boost again.

Here is the comparison. It looks like Humidity during night runs does lower the boost up top but strangly enough it is higher in the lower/midrange rpm

 

Interesting. Once i get my tune dialed back in, maybe i'll do some night/day comparisons. It's pretty humid here in FL so it would interesting to see if i have the same behavior you're seeing.