32 gtr & boost guage dramas

[djhatton]

g'day g'day peeps.

my factory boost guage in my 32 gtr isn't working.

can someone tell me if the sender is the little black box mounted to the firewall up high on the drivers side... ? and if so, where does the vaccuum line usually lead to for it... ?? .....or am i way off?

where are people usually t-piecing their vaccuum hoses for aftermarket boost guages in these cars.

cheers

david

[Godzilla32]

OK i can prolly help with this too. You are right, the black box that has a connector and a small tube running from it is for the stock guage. To run a mechanical aftermarket guage you need to t-piece the inlet pressure line to the intake mannifold. An easier one to t-piece would be the line going to the fuel pres. reg.

Again i hope i have helped.

Deren

[nedb]

Sorry to hijack, but my factory boost guage isn't working as well.

The hose that ran to the little black box on the firewall was cut and the aftermarket boost guage connected to it.

Are there any side effects for disconnecting the black box?

[Godzilla32]

Hey nedb no need to be sorry i feel like im taking over all of djhatton's posts anyway

So far as i can tell the only thing that happens when the black box is disconnected, is that the stock gauge wont function. Which prolly wouldnt make much diff to your gauge by the sounds anyway. If you want both the stock and aftermarket gauges to function you need to put a t-piece hose connector into the vacuum signal hose (the one that is now only going to your aftermarket gauge) and they will both operate.

Any other problems i'll try to help,

Deren

[djhatton]

hey where does this factory boost sender pipe supposedly lead to? mine's not going to anything and a dig around the plenum isn't finding me much... or am i looking in the wrong places?? i can find plenty of vacuum lines... just don't know where that factory one leads...

where's the best place to run a vacuum hose through the firewall for an aftermarket guage? i ahven't looked yet, but planning on fitting the one i've got lying around in the next few days...

cheers

d

[Godzilla32]

The original vacuum line for the gauge runs to the back of the engine (firewall) and connects to the back of the intake mannifold (not the collector/plenum). Its closer to the block..Just use one of the original sealed holes that are in the firewall..

[nedb]

Godzilla32 - Thanx for the reply.

Also, the wires coming out of the little black box they would be just telling the factory boost guage what boost to show, but would they lead to the ECU as well.

I guess what i'm trying to ask is, does ECU know what boost your running and if so where does the signal come from?