This is a write up of how to install DEFI BF series gauges on a GD impreza, using the triple meter hood. This install will be in, well, installments, as I don't have the mechanical capacity to do it all myself, so I'm going to tackle as much as I can, 1 step at a time, then later down the road, do the finishing touches when help is available.
These gauges are, in my opinion, top of the line JDM bling, unless you wanna go huge, spend 5 grand and get one of those STACK LCD clusters. They are electronic, with programmable warnings, data record and playback, and brightness control. They also have an opening and closing "ceremony", similar to what the STi gauge cluster does.
Here's where we start:
- 3 x 60mm DEFI BF amber gauges - Boost (in PSI), Oil Temp (Celcius), and Oil Pressure (PSI)
- DEFI Link Controller II (required to make the gauges work)
- DEFI Triple Gauge pod for GD impreza
![Image]()
The DEFI Hood originally comes in primer grey. I used a standard flat black trim spray paint and it did the job. You can see that I suck, even at spray painting (lets just see how the rest of the install goes), but those drip flaws are completely obscured once the gauges are in place, as you will soon see.
The gauges are available in both imperial and metric units. I choose Boost and Oil Pressure in imperial. Why? I'm just used to PSI, and 95% of the posts on all the forums reference to PSI. Oil Temp in celcius was the obvious choice for me, as I still have no clue or concept with Farenhiet units. A word of note, if you choose Imperial Oil temp, the sensor is 1/8" NPT, which is a different thread pitch than the 1/8" PT threads used in the engine block, you'll need an adapter. The imperial oil Pressure sensor is 1/8" PT, which will fit fine.
The triple gauge hood comes with 3 rubber gaskets - these are meant to hold the gauges in place. You put the gauges in the holes, then install the gaskets from behind, supposedly secure the gauges. They do an alright job, but I can see them shift out of place in time, so I put a dab of crazy glue to ensure security. You can also see that once in place, the gauges do a pretty good job of hiding my retarded painting skills.
![Image]()
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Now that the gauges are in place, its time to "daisy chain" them. These suckers need power, not just for illumination, but for operation as well. What's unique about them is that you can wire them in a "daisy chain", so that only 1 wire emerges from the gauge pod to the control unit. Pretty easy, as shown. You can see how the gauges connect to each other, and then a main line comes off one of the gauges, which will go down to the control unit.
![Image]()
Once installed, the main wire will plug in the the METER OUTPUT 2 plug on the controll unit (using the METER OUTPUT 1 plug will cause malfunction of the gauges, make sure you use METER OUTPUT 2)
![Image]()
So the next step is installing the pod, wiring up the Link Controller, and installing and wiring the various sensors.
Obviously, the pod replaces the clock in the centre of the dashboard. Its held in by clips. I pulled, gently but forcefully, on one side, and it began to pop off.
![Image]()
Underneath, there is a plug harness attached to the clock - this comes undone very easily.
![Image]()
You'll need to pull back the tape on the wire bundle to expose the wires a little bit better. The clock actually labels which wires are which, helps alot. From top to bottom -
BATTERY
GROUND
LIGHTS ON
IGNITION
![Image]()
Then take the power harness for the Link controller and tap the wires from the clock harness. I used the included tapping pieces which were really easy to use. They basically clamp the Link wires into the clock wires without having to do any cutting.
Harness wires tap into the following clock wires -
Red to 12V
Black to Ground
White to Lights on
Orange to ignition
Here's the finished product, a bit messy, but you get the idea:
![Image]()
I then ran the harness line from the clock area, thru the dash to underneath the driver's footwell, then to the controller. The harness plugs into DC SOURCE plug in the link controller. I also fed the gauge line (which connects the gauges to the controller) the same way, and plugged it into METER OUTPUT 2.
![Image]()
Now the money shot - the test. Do this before you put the pod in place, so that any wiring mistake can be corrected easily. HORRAAAY, MINE WORKS!!!
![Image]()
I then installed the pod into the dash. The pod is made of ABS plastic, so it doesn't flex very much, so be careful not to break the tabs off. I started at the front, and worked my way around - fits perfect - the finished product:
![Image]()
I then decided to tackle the Boost Gauge, as its the easiest one to do. I first started by going into the engine bay, and locating a firewall hole/rubber grommet - I chose the one behind the pedals. I ran the electrical line thru this grommet
![Image]()
Given that I had the stock boost gauge, the ByPass Valve line was already tapped - I used the existing "T" and attached the rubber line that eventually goes to the boost sensor. The "T" that comes with the DEFI gauge is too small to tap the BPV lines, so you'll need to find another one. The stock boost gauge one works perfect. The directions say to use as little of the rubber hose as possible.
![Image]()
That means finding a suitable location close by to mount the sensor. Directions also say that the "nipple" for the rubber hose should be facing downwards. The side of the fuse panel was the obvious choice.
![Image]()
The wire that ran thru the firewall plugs into the TURBO plug. I also mounted the Link controller using the 2 sided tape included in the kit.
![Image]()
After that, time for a test drive!!! Boost works flawless, with the PEAK function showing me hitting just under 17 psi Cobb Stage 2(thats after disconnecting the battery, which resets the ECU). The other two gauges indicate 0, with the warning LED flashing, indicating that the sensors are not connected. That will be fixed in my next installment, when I tackle those two other sensors.
![Image]()
Heres a video of the opening/closing ceremony
DEFI Startup - dscf1589.avi @ ZippyVideos.com - Free Video Webhosting
Next is installing and wiring the oil pressure sensor. I chose the location under the alternator, for ease of installation, and well, if Subaru thinks thats a good spot for a pressure sensor, then I'll do the same.
So here's the location of the stock sensor - you can see it just to the left, and underneath the alternator.
![Image]()
Time to then remove the alternator. The belt cover comes off with two bolts. The alternator itself is held on by two bolts. There is also a third that you should loosen off. This is the belt tensioner. I witness marked the location of the tensioner with a sharpie, then loosed it off. This slackens the belt, making removal of the alternator much easier. The two bolts then come off the alternator, and it comes out very easily.
![Image]()
You can see now that the oil pressure sensor is completely accesible. The wire slips right off, and I zip tied that wire off to the side. The sensor comes out using a wrench - its a little awkward, but I made it happen. Having a crows foot would have made it a lot easier.
![Image]()
Then take the DEFI sensor and wrap the threads with teflon tape.
![Image]()
That sensor screws right in - tightened it down pretty good - i didn't reef on it, but its in there good. You can also see an unpluged harness at the bottom - that's the crankshaft position sensor - i unplugged it because it gave me a little extra room for my wrenches - Don't forget to plug it back in!!
![Image]()
Alternator goes back in, wire the lines via the same routing as the boost gauge wires to the Link controller - Obviously, the wire plugs into Oil Pressure plug on the contrller.
![Image]()
Tada - it works - showing 100 psi on start - just like it supposed to. Let it idle for 5 minutes or so and check for leaks. Good to go!!
![Image]()
Ok, the final step is the oil temperature sensor. I chose to have this installed at the oil gallery plug "under" the intercooler. I threw the word under in quotations, because its location isn't really UNDER the intercooler. More on that later.
I tried to keep this article as comprehensive as possible, so us amature do it yourselfers could use this as a reference. I must apologize, the end of this article will probably come to most as a dissappointment, as I wasn't able to take many pictures of the final stage. Again, more on that later.
I chose to use this location because I find its the cleanest method of install. I'm sure the filter sandwich adapters work just fine, but I wanted to install these sensors and leave them alone. Using a sandwich filter exposes the setup every time you get an oil change done, increasing the possibilities of leakage. That arguement is another can of worms, so lets get on with the install.
If you look at the red turbo hose on the left side of the intercooler, sorta underneath, then look just to the right in that tight space. You'll see a bolt/plug with a hex hole. That's the gallery plug you want to get rid off. ITs an 8mm hex. To maximize working space, you'll probably want to remove the intercooler. There are several bolts you'll need to undo to do this:
![Image]()
You can see there are 2 main side bolts, 3 across the front that hold the black tubing, 2 bolts that attach the ByPass Valve, 1 clamp on the turbo, and 1 clamp on the throttle body. I would also recommend removing the strut bar to allow more movement. Its quite akward getting it off, but be patient and carefull, and it will eventually slide out.
You'll clearly see the gallery bolt at this point, just to the right of the turbo. So now you'll want to remove that bolt. As mentioned, its an 8mm hex, and its very, very hard to remove. Some have used an allen wrench, but I would recommend using a ratchet, using a hex socket on the end. A 6" or 10" extension is very usefull too.
TIP - make sure the hex bit is WELL SEATED in the hole. Give it a couple taps with a hammer just to make sure. If its not seated properly, you'll strip the bolt.
After removing the bolt, you need to install the Subaru OEM part. Its the threaded gallery plug and washer. The part numbers are (to be confirmed). The combo costs about 10 bucks at any subaru dealership.
Again, using the ratchet and extension, screw that in the hole where the plug used to be. Then the sensor goes in. If you have the DEFI METRIC sensor (in celcius), it will go in without a hitch. If you have DEFI IMPERIAL (farhenheit), you'll need a NPT to BSPT adapter to make it fit.
Recommend that you use a 14mm crowsfoot wrench to install this. It makes things a whole lot easier. Tighten it snugly, but do not reef it tight.
Hook up the harness as per the other gauges. Here's a pic of the temp sensor installed. It shows both the sensor, and the Subaru part. Also gives you a better idea where this actually is.
![Image]()
Re-install the intercooler. I found that slipping on the red turbo hose first, then working the throttle body section on after is easier.
AUTHOR'S NOTE: Ok, now for my confession. While I was doing this final stage, I made a huge, potentially costly mistake. I removed the intercooler as per my directions. When I went to remove the plug using my 8mm hex, and I didn't ENSURE THE BIT WAS SEATED. I rushed it, went ahead and started cranking. I stripped the bolt. The hole that was once a hex, was completely rounded. I tried everything to get it out. Flathead screwdrivers, torx bits, everything....I thought to myself, what the hell am I gonna do now? Get a sandwich adapter? Tap the oil pan? Try to "T" off the oil pressure sensor location?
I went to my local mechanic to have a look. He managed to chisel out the bolt, and then went ahead and installed the Subaru part/sensor assembly. He did it WITHOUT removing the intercooler. So it can be done. The surrounding hoses are flexible enough that with a 10" extension, and a crowsfoot, you can complete this install with relative ease. The intercooler is a bi*ch to re-install, so this method may be a much easier option.
This explains my lack of pictures for this part of the process.
So you there you have it guys. From start to finish. Again, my apologies for the half-assed final stage, but I learned my lesson. Take the extra few minutes and do it right the first time. Don't rush and end up like me, desperate for options. I hope you find this article usefull, and hopefully turns into a sticky.
****Just a quick update***** Some complain that using the clock wiring causes the ALARM to go off when your car is turned off (like when listening to the radio etc...) Here's a quick fix.
- Do a quick DATA record of your car idling.
- When you turn your car off, replay your data, then press PAUSE
- Bingo, no more beeping.
If anyone has any questions, PM me.
These gauges are, in my opinion, top of the line JDM bling, unless you wanna go huge, spend 5 grand and get one of those STACK LCD clusters. They are electronic, with programmable warnings, data record and playback, and brightness control. They also have an opening and closing "ceremony", similar to what the STi gauge cluster does.
Here's where we start:
- 3 x 60mm DEFI BF amber gauges - Boost (in PSI), Oil Temp (Celcius), and Oil Pressure (PSI)
- DEFI Link Controller II (required to make the gauges work)
- DEFI Triple Gauge pod for GD impreza
The DEFI Hood originally comes in primer grey. I used a standard flat black trim spray paint and it did the job. You can see that I suck, even at spray painting (lets just see how the rest of the install goes), but those drip flaws are completely obscured once the gauges are in place, as you will soon see.
The gauges are available in both imperial and metric units. I choose Boost and Oil Pressure in imperial. Why? I'm just used to PSI, and 95% of the posts on all the forums reference to PSI. Oil Temp in celcius was the obvious choice for me, as I still have no clue or concept with Farenhiet units. A word of note, if you choose Imperial Oil temp, the sensor is 1/8" NPT, which is a different thread pitch than the 1/8" PT threads used in the engine block, you'll need an adapter. The imperial oil Pressure sensor is 1/8" PT, which will fit fine.
The triple gauge hood comes with 3 rubber gaskets - these are meant to hold the gauges in place. You put the gauges in the holes, then install the gaskets from behind, supposedly secure the gauges. They do an alright job, but I can see them shift out of place in time, so I put a dab of crazy glue to ensure security. You can also see that once in place, the gauges do a pretty good job of hiding my retarded painting skills.
Now that the gauges are in place, its time to "daisy chain" them. These suckers need power, not just for illumination, but for operation as well. What's unique about them is that you can wire them in a "daisy chain", so that only 1 wire emerges from the gauge pod to the control unit. Pretty easy, as shown. You can see how the gauges connect to each other, and then a main line comes off one of the gauges, which will go down to the control unit.
Once installed, the main wire will plug in the the METER OUTPUT 2 plug on the controll unit (using the METER OUTPUT 1 plug will cause malfunction of the gauges, make sure you use METER OUTPUT 2)
So the next step is installing the pod, wiring up the Link Controller, and installing and wiring the various sensors.
Obviously, the pod replaces the clock in the centre of the dashboard. Its held in by clips. I pulled, gently but forcefully, on one side, and it began to pop off.
Underneath, there is a plug harness attached to the clock - this comes undone very easily.
You'll need to pull back the tape on the wire bundle to expose the wires a little bit better. The clock actually labels which wires are which, helps alot. From top to bottom -
BATTERY
GROUND
LIGHTS ON
IGNITION
Then take the power harness for the Link controller and tap the wires from the clock harness. I used the included tapping pieces which were really easy to use. They basically clamp the Link wires into the clock wires without having to do any cutting.
Harness wires tap into the following clock wires -
Red to 12V
Black to Ground
White to Lights on
Orange to ignition
Here's the finished product, a bit messy, but you get the idea:
I then ran the harness line from the clock area, thru the dash to underneath the driver's footwell, then to the controller. The harness plugs into DC SOURCE plug in the link controller. I also fed the gauge line (which connects the gauges to the controller) the same way, and plugged it into METER OUTPUT 2.
Now the money shot - the test. Do this before you put the pod in place, so that any wiring mistake can be corrected easily. HORRAAAY, MINE WORKS!!!
I then installed the pod into the dash. The pod is made of ABS plastic, so it doesn't flex very much, so be careful not to break the tabs off. I started at the front, and worked my way around - fits perfect - the finished product:
I then decided to tackle the Boost Gauge, as its the easiest one to do. I first started by going into the engine bay, and locating a firewall hole/rubber grommet - I chose the one behind the pedals. I ran the electrical line thru this grommet
Given that I had the stock boost gauge, the ByPass Valve line was already tapped - I used the existing "T" and attached the rubber line that eventually goes to the boost sensor. The "T" that comes with the DEFI gauge is too small to tap the BPV lines, so you'll need to find another one. The stock boost gauge one works perfect. The directions say to use as little of the rubber hose as possible.
That means finding a suitable location close by to mount the sensor. Directions also say that the "nipple" for the rubber hose should be facing downwards. The side of the fuse panel was the obvious choice.
The wire that ran thru the firewall plugs into the TURBO plug. I also mounted the Link controller using the 2 sided tape included in the kit.
After that, time for a test drive!!! Boost works flawless, with the PEAK function showing me hitting just under 17 psi Cobb Stage 2(thats after disconnecting the battery, which resets the ECU). The other two gauges indicate 0, with the warning LED flashing, indicating that the sensors are not connected. That will be fixed in my next installment, when I tackle those two other sensors.
Heres a video of the opening/closing ceremony
DEFI Startup - dscf1589.avi @ ZippyVideos.com - Free Video Webhosting
Next is installing and wiring the oil pressure sensor. I chose the location under the alternator, for ease of installation, and well, if Subaru thinks thats a good spot for a pressure sensor, then I'll do the same.
So here's the location of the stock sensor - you can see it just to the left, and underneath the alternator.
Time to then remove the alternator. The belt cover comes off with two bolts. The alternator itself is held on by two bolts. There is also a third that you should loosen off. This is the belt tensioner. I witness marked the location of the tensioner with a sharpie, then loosed it off. This slackens the belt, making removal of the alternator much easier. The two bolts then come off the alternator, and it comes out very easily.
You can see now that the oil pressure sensor is completely accesible. The wire slips right off, and I zip tied that wire off to the side. The sensor comes out using a wrench - its a little awkward, but I made it happen. Having a crows foot would have made it a lot easier.
Then take the DEFI sensor and wrap the threads with teflon tape.
That sensor screws right in - tightened it down pretty good - i didn't reef on it, but its in there good. You can also see an unpluged harness at the bottom - that's the crankshaft position sensor - i unplugged it because it gave me a little extra room for my wrenches - Don't forget to plug it back in!!
Alternator goes back in, wire the lines via the same routing as the boost gauge wires to the Link controller - Obviously, the wire plugs into Oil Pressure plug on the contrller.
Tada - it works - showing 100 psi on start - just like it supposed to. Let it idle for 5 minutes or so and check for leaks. Good to go!!
Ok, the final step is the oil temperature sensor. I chose to have this installed at the oil gallery plug "under" the intercooler. I threw the word under in quotations, because its location isn't really UNDER the intercooler. More on that later.
I tried to keep this article as comprehensive as possible, so us amature do it yourselfers could use this as a reference. I must apologize, the end of this article will probably come to most as a dissappointment, as I wasn't able to take many pictures of the final stage. Again, more on that later.
I chose to use this location because I find its the cleanest method of install. I'm sure the filter sandwich adapters work just fine, but I wanted to install these sensors and leave them alone. Using a sandwich filter exposes the setup every time you get an oil change done, increasing the possibilities of leakage. That arguement is another can of worms, so lets get on with the install.
If you look at the red turbo hose on the left side of the intercooler, sorta underneath, then look just to the right in that tight space. You'll see a bolt/plug with a hex hole. That's the gallery plug you want to get rid off. ITs an 8mm hex. To maximize working space, you'll probably want to remove the intercooler. There are several bolts you'll need to undo to do this:
You can see there are 2 main side bolts, 3 across the front that hold the black tubing, 2 bolts that attach the ByPass Valve, 1 clamp on the turbo, and 1 clamp on the throttle body. I would also recommend removing the strut bar to allow more movement. Its quite akward getting it off, but be patient and carefull, and it will eventually slide out.
You'll clearly see the gallery bolt at this point, just to the right of the turbo. So now you'll want to remove that bolt. As mentioned, its an 8mm hex, and its very, very hard to remove. Some have used an allen wrench, but I would recommend using a ratchet, using a hex socket on the end. A 6" or 10" extension is very usefull too.
TIP - make sure the hex bit is WELL SEATED in the hole. Give it a couple taps with a hammer just to make sure. If its not seated properly, you'll strip the bolt.
After removing the bolt, you need to install the Subaru OEM part. Its the threaded gallery plug and washer. The part numbers are (to be confirmed). The combo costs about 10 bucks at any subaru dealership.
Again, using the ratchet and extension, screw that in the hole where the plug used to be. Then the sensor goes in. If you have the DEFI METRIC sensor (in celcius), it will go in without a hitch. If you have DEFI IMPERIAL (farhenheit), you'll need a NPT to BSPT adapter to make it fit.
Recommend that you use a 14mm crowsfoot wrench to install this. It makes things a whole lot easier. Tighten it snugly, but do not reef it tight.
Hook up the harness as per the other gauges. Here's a pic of the temp sensor installed. It shows both the sensor, and the Subaru part. Also gives you a better idea where this actually is.
Re-install the intercooler. I found that slipping on the red turbo hose first, then working the throttle body section on after is easier.
AUTHOR'S NOTE: Ok, now for my confession. While I was doing this final stage, I made a huge, potentially costly mistake. I removed the intercooler as per my directions. When I went to remove the plug using my 8mm hex, and I didn't ENSURE THE BIT WAS SEATED. I rushed it, went ahead and started cranking. I stripped the bolt. The hole that was once a hex, was completely rounded. I tried everything to get it out. Flathead screwdrivers, torx bits, everything....I thought to myself, what the hell am I gonna do now? Get a sandwich adapter? Tap the oil pan? Try to "T" off the oil pressure sensor location?
I went to my local mechanic to have a look. He managed to chisel out the bolt, and then went ahead and installed the Subaru part/sensor assembly. He did it WITHOUT removing the intercooler. So it can be done. The surrounding hoses are flexible enough that with a 10" extension, and a crowsfoot, you can complete this install with relative ease. The intercooler is a bi*ch to re-install, so this method may be a much easier option.
This explains my lack of pictures for this part of the process.
So you there you have it guys. From start to finish. Again, my apologies for the half-assed final stage, but I learned my lesson. Take the extra few minutes and do it right the first time. Don't rush and end up like me, desperate for options. I hope you find this article usefull, and hopefully turns into a sticky.
****Just a quick update***** Some complain that using the clock wiring causes the ALARM to go off when your car is turned off (like when listening to the radio etc...) Here's a quick fix.
- Do a quick DATA record of your car idling.
- When you turn your car off, replay your data, then press PAUSE
- Bingo, no more beeping.
If anyone has any questions, PM me.
Thans again for such a wonderful how to thread 
