boost gauge sputtering???

[MIKES86GN]

i've tried to understand this problem, or maybe it's not even a problem...if i ease the car into it the boost gauge is steady & holds fine..but if i mash it the gauge seems tobe shaking like its fluctuating some ....i'm only 18 pds
When we boost these cars is the boost gauge supposed tobe set ,,meaning if u have the w/g open @ 15 pds will the needle stick to 15...i might be going crazy but since i'm new to these car's i'm open to all advice....it has a boost gauge , a p70, & dfi ....so she boogies.....

 

[buickpower]

what do you have for boost control? sometimes cars with grainger valves/ quick spool valves have boost spike and creep problems. trouble is they spool too fast and cannot act fast enough to get a steady handle on the boost level.

the boost gauge if calibrated correctly from the manufacturer will just read whatever is applied to it. this assumes that it is in good shape and has a non-leaking boost source.

 

[MIKES86GN]

i have a manual boost gauge ..like the one that j c sells...i personally think that the turbo is spooling so fast that the gauge is having trouble reading it correctly...other than that is she great...beside's the rear main seal leaking...

 

[marred4life]

check all your vaccume hoses, they might have some cracks in them, but make sure you check them ALL!!!, i had the same problem and found some of my vaccume hoses worn and beat, i replaced all of them and am holding boost with no creeps :biggrin:

 

[MIKES86GN]

i am going to check all the lines..go over all the easy stuff 1st...

 

[MIKES86GN]

Is This A Common Problem???

 

[corsair231]

Worst case senario. Wiped cam lobes. This is how mine started acting when the cam went south. Car still pulled hard and easing into boost was hardly no flutter but flooring it the needle would vibrate wildly. May be your problem, hope not though. Might just be compressor surge.