Idle Vacuum pressure question
#1
Addict
Lifetime Rennlist
Member
Lifetime Rennlist
Member
Thread Starter
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
What is/should the vac pressure read(on my zeitronix) in lbs of pressure? What is normal or average? Mine used to be about -19 to -21.x. It is now between 14.6x and 16.x. The turbo is spooling late.
TIA
TIA
#4
Addict
Lifetime Rennlist
Member
Lifetime Rennlist
Member
Thread Starter
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
When I come off of hard throttle, it goes back to 20.X, but then settles back at about 16. For the life of me I still can't find the leak. Any ideas?
#7
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Vac line to the front of the throttle body, line to diverter, oil filler, vac lines inside the car for heater/AC, connection to the wastegate, idle controller, lines to fuel canister purge lines.
Might have to do a pressure test.
Might have to do a pressure test.
Trending Topics
#10
Rennlist Member
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
I had 16+ on the old (worn) motor, and get 18 on the new motor -- that's fully warmed up. With an aftermarket cam, those numbers went down quite a bit. Don't ask me why, but I've noticed the vacuum varies a bit with the ignition timing and AFR also...
#13
Addict
Lifetime Rennlist
Member
Lifetime Rennlist
Member
Thread Starter
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
hmmm...prior to changing out the head and HG, I was at 20 ish. Same bottom end and I'm at 14.X to 16.X. The car definitely seems to be running rich. I'll know AFR's tomorrow.
#14
Rennlist Member
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Probably just have a leak somewhere, but check the tune and make sure your cam timing is correct too...
#15
Addict
Lifetime Rennlist
Member
Lifetime Rennlist
Member
Thread Starter