wont go above 5 psi today!!!!
 

well looks like the gms1 hits me with the first shot!!! noticed this morning she wont go above 5 psi, more like 4 psi. just sits there and is slow as heck!!! maybe issue with cp/intercooler or one of sensors getting loose??? 22k miles and no other mods except muff delete but thats it

My buddy had the same problem.

His problem was that his catalytic converter had basically dicinegrated (Spelled wrong (N) ) within its self and was blocking air flow.
So check for blockages?

This happened to me when the wastgate actuator came loose and had a bad connection.

ya theres a bad connection or part like rukkee said. Theres been a few threads with this issue recently.

Mine did that and it was the MAF malfunctioning. Just adding to the list of things it could be, unfortunately.

I had the same problem...

https://www.cobaltss.net/forums/general-cobalt-68/09-ss-tc-new-engine-%40-24-xxx-miles-219564/

It happen to me because of boost leaks coming out of the Injen charge pipe. Yup t-bolt were put on later to prevent it from happening again.

also check the sensor on the cold side piping... if it gets wet from the AC it will cause this problem... a buddy of mine just zip tied it to another sensor and it hasnt done it sense

mine has done that before, it turned out that i hit something and punched a hole in my intercooler with the frame

Basically, if any number (in the hundreds) of issues arise that the computer doesn't like, it dumps the whole system into this mode. In other words... 5psi boost does not equal a specific problem. You're going to need to parse the error codes to see what went wrong that would have caused the limp mode.

Fancy word you to there: parse.