Thread: zero boost on aftermarket guage

so i finally hooked up my boost guage on friday. its an Equuis from oreillys. so it reads zero when not running, -15 to -19 at idle, -10 and normal throttle, and ZERO and WOT... DIC guage reads all bars full boost. and i know im getting boost because its fast and feels like the boost is kicking in and the blower is loud. did i hook it up to the wrong vacuum source? i figured any vacuum source would get boost, maybe not. i hooked it up to the easiest spot to reach since i was being rushed to leave by my wife. its that 3 connecting thing on top of the blower, its connected inline of the middle one, the one next to the line that goes to the bbv. im thinking of trying the bbv line and if that doesnt work then the one by the map sensor?

it might be where you sourced the vac from
I would put a T in at the line right at the map sensor coming out the back

Originally Posted by TorqueAutoMotiv

it might be where you sourced the vac from
I would put a T in at the line right at the map sensor coming out the back

Exactly what I did!

Originally Posted by hourang

did i hook it up to the wrong vacuum source? i figured any vacuum source would get boost, maybe not. i hooked it up to the easiest spot to reach since i was being rushed to leave by my wife. its that 3 connecting thing on top of the blower, its connected inline of the middle one, the one next to the line that goes to the bbv. im thinking of trying the bbv line and if that doesnt work then the one by the map sensor?

Think this through, don't just try this and that. That vacuum manifold you connected to is before the blower rotors, so how's it supposed to see boost?

Originally Posted by Scimmia

Think this through, don't just try this and that. That vacuum manifold you connected to is before the blower rotors, so how's it supposed to see boost?

im too new to these cars to know the routing of the lines, havent messed with it much besides the air filter. its right before the bbv, so the bbv doesnt see boost? i knew this was most likely the problem and would have fixed it but i wanted more information on why so i can learn more about the complex vacuum system on these cars.

Originally Posted by hourang

im too new to these cars to know the routing of the lines, havent messed with it much besides the air filter. its right before the bbv, so the bbv doesnt see boost? i knew this was most likely the problem and would have fixed it but i wanted more information on why so i can learn more about the complex vacuum system on these cars.

The black canister is just the actuator for the BBV, so no, it doesn't see boost. It's really not that complicated, you have the inlet for the supercharger, the rotors, and the outlet. You're connected to the inlet, which is before the air is compressed. You need to connect AFTER the rotors.

Originally Posted by Scimmia

The black canister is just the actuator for the BBV, so no, it doesn't see boost. It's really not that complicated, you have the inlet for the supercharger, the rotors, and the outlet. You're connected to the inlet, which is before the air is compressed. You need to connect AFTER the rotors.

ah i see. thanks!

stupid t fittings. tried to tap into the t fitting under the snout and the t fitting just broke like it was plastic. have it rigged with electrical tape right now, but will need to replace them. anyone replace all their plastic lines and know what size t fittings and hoses you need? i know there are 2 different sizes i need because the connector under the snout is big and the one on the fpr? is small.

i used rubber hose and some plastic vac line T's I got from the autoparts store.

Originally Posted by Lawngoose

i used rubber hose and some plastic vac line T's I got from the autoparts store.

did you have to get 2 different sizes?

No, i used some small rubber hose... maybe 1/8" ... stuck it over the nipple under the snout... then using the plastic, barbed T... used two more pieces of rubber hose to connect to the plastic lines.

Would it help better if I got you a picture?

Originally Posted by Lawngoose

No, i used some small rubber hose... maybe 1/8" ... stuck it over the nipple under the snout... then using the plastic, barbed T... used two more pieces of rubber hose to connect to the plastic lines.

Would it help better if I got you a picture?

oh im saying i want to replace all the plastic lines with rubber and brass Ts.