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intake pressure level at idle?



My 1988 MC-I engine has for the past year had an intake pressure of 0.3
bar at idle and 0.2 bar at deceleration. Now it has gone up to 0.5/0.6
bar at idle when cold and 0.4 when hot, and unchanged 0.2 bar at decel..
Idle has also become at bit rough. The maximum pressure is unchanged at
1.4 bar.

Am I experiencing the famous vacuum-leak?

I pulled the fault codes and tried also pointing an unlit torch at the
vacuum-lines, but no luck.

What kind of idle pressure would be normal for my engine?
Couldn't find anything more precise than "between 0.2 and 0.8 bar" in
Bentley's.

Could the unchanged maximum boost indicate that the potential leak is on
the suction side of the turbo?

Any ideas why there is a 0.1 bar difference under cold vs. hot
conditions?

Your thoughts are greatly appreciated. ;)

TIA
Flemming Christensen
Denmark

PS. did a little table for your convience:
0.1 bar = 1.45 psi
0.2 bar = 2.90 psi
0.3 bar = 4.35 psi
0.4 bar = 5.80 psi
0.5 bar = 7.25 psi
0.6 bar = 8.70 psi
1.4 bar = 20.3 psi