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Discussion Starter · #1 ·
Under what circumstances, if any, should the boost pressure go into the red? Since I fixed my vac leak I've noticed it doing this under hard acceleration in higher geaars, about halfway into the red. Is this a problem, or is the guage too inaccurate to be sure?
 

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I think most people with a standard car find that the boost will go into the red when the pedal is first floored and it will than drop off and hold around the divide between the red and the yellow if the pedal is kept down. I think the use of something like a bleed valve can help to keep it in the red if wanted. Anyone find their car does differently to this?
 

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Discussion Starter · #3 ·
Phew that's OK then. I can understand that a vac leak would also be a boost leak under boost, so I can see why boost might increase after fixing a leak. I was just worried that that the vac leak might have been masking a stuck wastegate or faulty APC boost control, but if this is normal behaviour I can stop worrying Thanks.
 

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My car, will hold the boost off the top of red until just over 3000rpm. Not as consitently as it used to, it probably depends on wastegate spring stifness and whether or not the ECU detects any pinking or piston knock under hard acceleration.
 
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