Mitsubishi 3000GT Service Manual page 437

INTAKE AND EXHAUST - Intake Manifold
INSPECTION
Check the following points; replace the part if a problem is
found.
INTAKE MANIFOLD CHECK
. (1) Check for damage or cracking of any part.
(2) Clogging of the negative pressure (vacuum) outlet port,
or clogging of the gas passages.
(3) Check deflection of installation surface with straight edge
and thickness gauge.
Standard value: 0.15 mm (.0059- in.) or less
Limit: 0.2 mm (.008 in.)
TSB Revision