defi racer boost gauge sensor to mazda boost sensor?
 

Hey guys, just got my defi racer boost gauge in today and the directions say to hookup the vacuum hose to the defi sensor and then to a t-junction which connects to the surge tank. Seems like all of the how to boost gauge sites base their how to on the basis that you are using a vacuum hose all the way to the gauge and so they hook it up at the UIM nipple and run it back to the gauge.

My question is.. Do I do the same with my defi sensor? i.e. Run the vacuum hose from the UIM nipple directly to the sensor or do I use the t-junction and splice into the vacuum hose that runs into the mazda boost sensor from the TB?

Any help would be greatly appreciated, thanks.

For a boost gauge, use the extra vacuum nipple on the upper intake manifold. It will give true and proper readings. I don't recommend T-ing into the stock boost sensor vacuum line - that is a VERY critical line, and if that T fails or a line pops off, that could cause engine damage.

Check the FAQ, there's plenty on installing boost gauges.

Dale

Re:
 

Thanks Dale.

+1 to what dale said. I have the same gauge as you and I hooked it up to the extra nipple on the UIM. Gives a very accurate reading.

Wiring help
 

Okay, I'm ready to start hooking up the power wires for the gauges and would like to know where would be a good location. I've searched threads and found that the ash tray light is not a good wire to use a constant +12v wire. Apparently, the large blue molex connectors under the steering wheel are better for this.

So, thats 1 wire out of the way, but I still have 2 more to go...

12v Battery wire (red) ==> 1st gauge to molex (1) and 2nd gauge to molex (2)
12v Ignition On (orange) ==> help please
12v Illumination (white) ==> help please
Ground ==> I got this one =)

I've also looked at the wiring schematics from the repair manual, but that isn't really helping me so any help would be greatly appreciated.