I've searched many time now and come up with almost nothing on raising the vacuum. It sits pretty damn low at idle (15inHg) , and it worries me becasue I feel like I am not gettin all that much power off my old/new TII coil and mallory 6a cd ignition system, even though the car seems to be ideling just fine...a bit smoother if anything with the new parts but it doesn't feel llike its pullign any harder...slower if anything...and my last leading coil as fried. THE Mallory is workign properly becasue the light is on when the car is running meanning it is gettin a proper trigger signal. So whats a way for me to raise my vacuum....


I know I shoudl recheack all my vacuum hoses
check all my gaskets
check all the intake pipe connectoins
check my UIM and LIM bolts...
check if the turbo is properly tightened onto the car.
check housing compression?

THis is my set up.

DP, CB
pullies
no A/C
no air pump
Denso high feed fuel pump
new all trailing plugs
new magnacor wires
TII leading coil and mallory 6a CD
new vacuum hose job
By passed the solenoids at the front of the UIM.

 

15 vac @ what rpm???

i get 15-16hg @ 740-760 and 20hg @ 900-1k

so u should be fine, unless u get those #'s at 750

GL man

 

actually i get those numbers at about 900-1000 rpm.

 

That seems like a normal idle inhg!
I usually get between 14-16

JP

 

Thats pretty darn good. Im ported and Im happy with 12 to 14 that I get.

 

going by the vacuum in the boost gauge is not vey acurate sinse it can change depending on elevation and/or wheather.

 

I guess I guess, but I sweare it seems a little less powerful than usual especially after the ignition change. Maybe my cat is clogged up by now? time ot get a mid pipe on ebay haha

 

No air pump - that's your problem.

The stock ECU compensates for the extra air injected in the manifold. Running with no air pump will give you some bucking at throttle tip-in, a rougher idle, and a lower idle vacuum.

If you can actually re-install the air pump without a huge effort, it might be worth it to see the difference. Personally I'd go nuts running a stock ECU without one. I accidentally blew the fuse for the air pump circuit a while back and the car drove like crap. The ECU uses the oxygen sensor for feedback at light load and idle, and it "fakes" the mixture a bit since it expects the reading to be leaner due to the extra air being pumped in the manifold.

Dale

 

hmmmmwell the thing is my plug to the air pump snappe doff my wires so yeahh......good ol shitty *** wiring harness from hell.