only90s

I can hear a whistle towards the back of my motor and think I have a big vacuum leak...My boost gage reads like between 15-20 on the vacuum side when driving down the road and when I get on it....it will go back to 0.

Problem is I have a 9lb supercharger on it and it wont go past 0...could the vacuum leak cause this...the supercharger appears to be working fine...it was building 9lbs of boost last time I really got on it last week.


Thanks

aode08

well when you did that intake swap, you didnt follow the bolt torque pattern for your lower and upper manifolds, so now you have a leak.

92hatchLX

Are you sure that your PCV system doesn't have a leak in it???

only90s

I have checked every line I could see..and put some silicone on some as well...I even tried to tighten my upper and lower intakes and they were tight...I got 1/4 turns on two of the upper bolts that is it...

I can still hear a whistle sound around the intake so that might be it..

I am going to try the Carb Cleaner trick later today around the intake and PCV

Called Powerdyne an they were useless(it was on car when I bought it..never would have went with it)

92hatchLX

powerdyne's aren't bad from what I've heard. I did a Powerdyne install on a 92 GT the other day and nothing really fit, but we got it to work. Sounded good and it seemed to perform good.

only90s

This is related to my vacuum problem..

My gauge indicates about 10 on the vacuum side at idle and then drops to about 20 while driving down the road..it will then fluctuate between 10-20..until I hit the throttle and the supercharger kicks in..and then the guage stops at 0...

Could it be a faulty guage instead of the vacuum leak I am looking for..

Any help would be appreciated. Thanks