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Re: Weird scary boost fun...

> I'll bet you a Fat Tire (beer) that the there is a crack in the vacuum line
> going to the ECU, probably right where  the cloth-covered rubber hose is
> clamped at the intake manifold.   Boost opens the crack, vacuum pulls it shut
> again. The cloth holds it together so its hard to find.  Must be a small line
> that is broken/disconnected and keeping the ECU from knowing what the
> manifold pressure is.  If you had a large leak (like IC to throttle body),
> the display would be correct and you wouldn't get much boost. 

> I doubt _very_ much you pressure sensor is bad.  They either work or they
> don't and generally fail reading either full high or full low, never
> atmospheric.  BTDT, I've repaired five Audi ECU's with bad MAP sensors, but
> have never seen a failure such as you describe.  

I'd tend to agree... and the dash guage would be seriously sick too
since it's implying that it reads 0.8 at atmospheric.