Low boost/lack of power MC2-engine (MC dual knock)

[David Michael]

One way to check to see if its a boost leak or other problem is to
**temporarily"" plumb the wastgate so that you can keep it open with a hend
held vacuum pump.  I think you need to apply vacuum to the bottom of the
wastegate diaphragm to do that (don't have a plumbing diagram in front of
me).  Be VERY careful no to grenade your engine if you do this (your fuel
cut-off SHOULD prevent this, but ya never know). In any case, when the
diaphragm in my wastegate tore, my 200QA would build boost like crazy -
right up til I slammed into the fuel cut-off.

Some other thinks to check that may be temp. related - valve cover gasket
(big vacuum leaks); sticky  WGFV; bad multi-function temp switch (will limit
boost if it thinks the car is overheating - and these go bad).

When my lower IC hose went, you could easily HERE the boost leak  -
there  was a loud PSCHHHHHH whever I accelerated, and lots of black smoke
from too rich mixture.

Good luck

Dave
'90 200QA MC2 240,000 miles