[s-cars] Overboost and fault codes

[Dave Forgie]

Classic symptoms of a blown cross-over tube to intercooler "Michelin Man" 
hose.  Oil accumulates in the valleys of the hose and rots the rubber.  
Eventually, under boost these hoses split and release air that went past 
the MAF but then doesn't get to the engine.  The decreased air causes 
the engine to run over rich and the ECU to put you into limp home mode.

Solution:  Pressure test boost hose system from turbo to throttle body.  
Replace offending parts and hoses.  Most people with RS2 levels of boost
 are running Samco silicon hoses that do not rot and are super strong. 
However, new or good condition OEM rubber hoses still work even at 
higher boost levels, e.g. 26 psi.

HTH

Dave F.