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Re: removing vaccuum hose from ECU

> Can the engine run in this condition?

It can probably run, but it will be difficult or impossible to start and will run
like s***.  Removing the hose will do two things:

1) Give you a sizable vacuum/pressure leak 
2) Make the computer think the manifold pressure is approximately 1.0
bar at all times.
3) Perhaps some other things that are unique to the S4
engine-management system that I don't know about.  The ECU may just
shut the car down under these conditions when it realizes it can't sense
manifold pressure.

I don't know about the specifics of the S4 computer but on my '86 5kcstq
when the ECU hose came inadvertently detached the car would not idle
or start using the starter (you had to bump-start it while you were
already moving) AND you had to keep your foot in the gas at all times to
keep the engine from dying, AND the engine would run at the maximum
boost level permitted by the wastegate spring (the computer couldn't
dynamically control the boost via the WG solenoid).  It was horrible.  Why
would you want to do such a thing?

Best Wishes,

'86 5KCSTQ