Help 1psi of boost!

[swimshady906]

Whenever i'm on the gas i only get one psi ... it shoots from 30-25 psi of vac to 1 of boost when i floor it... in any gear. The vac reads correctly and sits at zero when it's off so the gauge reads right... what do you think the problem is?

[808Camry]

a leak.

[Yanks0114]

does everyone else vac that low?

At the lowest I vac at 22-24.

And i agree that its a leak or the line going to the boost gauge is kinked

[swimshady906]

Would vac. lines under the hood being incorrect cause something like this ( wastegate is partially open?)

[808Camry]

Yea maybe something might be sticky too, but I think its a kink or a leak

[Astro]

I had something similar and it turned out to be a kink in the line to the gauge.

[swimshady906]

I just checked the line to the gauge and just sorta let it out around through the window so there was no way it could kink... still only reads 1 - 1.5 psi. It spikes upto about 6 when i shift though, and the vac is 20 at idle and 25ish in gear off the throttle. Any thoughts?

[JoeB]

Mine read like that when I used the normal fat rubber vacuum line. Then I switched to the skinny clear tube and it reads correctly. -JoeB

[swimshady906]

I have the skinny one. When you guys are boosting... does it just hit 4 right away and stay there?

[Mole]

test on another gauge?

[swimshady906]

Tested another gauge that we know is accurate and it read 2ish. What to do?

[JoeB]

There aren't really a lot of factors to consider here. You might be overlooking something. My bet is a leak in one of the vacuum hoses. Maybe one that without pressure seems to be ok.Has it ever read properly for you? Where are you tapping to get your boost reading from? When I tapped off the vacuum tree, I got readings like that, I had to tap off the sc housing to get a good reading. -JoeB

[Vampire]

I assume you have a 5 spd?? You probably already know that once you accelerate through 3400 at WOT and keep the pedal to the floor, you should see full boost. If not you could have:

1. Incorrect vacuum hose hookup.
2. Incorrect EBC hookup.
3. Vacuum hose leak.
4. Bad bypass actuator.
5. Vacuum leak somewhere in the intake system although you would see other symptoms too. Not too likely.

I would recheck all the hoses and the routing, the EBC wiring etc. Then a few simple tests you can do are to remove the actuator vacuum hose while the car is idling. If it goes all the way to the stop, then the bypass is okay. Before I got a boost gauge, I put a little masking tape on the actuator stop and arm then drove it. If the tape on the arm was moved, you know the SC is trying to close the bypass and give boost. If the tape on the stop shows contact, you know you got full boost becasuse the actuator arm went to it's full travel.

Did you do anything to the car before you hooked up the gauge? I find that the last thing I did probably caused the problem I am seeing now. Good luck.

[swimshady906]

Thanks guys for all your help. Im banking on the problem being #2. Ive checked and rechecked trhe vac lines and the are all correct. Im going to hose clamp some of the looser ones. Ive unhooked the accuator and it pops open all the way so i know it is ok. Im going to try a few more things. THanks again.