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Oil pressure sensor install (in galley plug)

85K views 14 replies 4 participants last post by  Alex_1973 
#1 · (Edited by Moderator)
The purpose of this write up is to show the way I believe is best to install a oil pressure sensor. There are 3 most common places to put your sensor or sending unit.

1. In a oil filter sandwich adapter plate.
This is a plate with threaded holes in it for sensors, sending units, or plugs. It screws on where the oil filter does from the factory and then you screw your oil filter to that.

2. Rear galley plug.
This is simply a plug in the engine block that goes to a oil passage. It is located between the outlet of the turbocharger and the intercooler if your looking straight down at the engine.

3. Front galley plug.
This is the same as the rear but at the front of the engine just to the left of the alternator if your standing in front of the car. The only difference between this plug and the rear one is this one is threaded with a factory dummy light sensor in it.

I prefer using the front oil galley plug for my sensor/sending unit for a few reasons. One is because it is cheaper. The most you would have to buy extra to use this location is another plug with a different thread hole in it. I got a prosport one for $13 shipped. This is much cheaper than a sandwich adapter! A sandwich adapter also adds extra parts which raises the risk for a leak, can have clearance issues, and puts your oil filter a little closer to the ground.

While there may not be much of a pressure difference I prefer the front galley plug because it is only inches from the oil pump. The oil passages branch off before they get to the rear galley plug so, this may cause a slight difference (probably not enough to make much if any difference) in pressure readings between the front and rear galley plug locations. My opinion is that the rear galley plug location is better than a sandwich adapter but, not as good as the front galley plug. With all that said you can make your own decision on where to mount your hardware. Now on to the install.
 
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#2 ·
Here is the hardware I used. The galley plug itself has BSPT threads and the hole where the sensor goes is pipe thread. Most Aftermarket sensors/sending units are NPT thread. This is why you have to get another plug. The prosport one has NPT threads.
 

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#3 ·
You will have to remove the alternator to access this so first disconnect your battery. I hate how my car runs while it is relearning after a battery disconnect so I just taped up the power wire going to the alternator.

Now take the 10mm bolt on the left side of the alternator cover out.
 

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#11 · (Edited)
Unplug the wire from the sensor. Remove the sensor with a 24mm deep well socket. You can either relocate this sensor to the rear galley plug, make a T-fitting so you can use your new sensor and this one both, or do away with it all together. Removing it will not cause any dash lights to come on. This sensor only turns a light on when the oil pressure gets down below 5psi anyway. If you get that low your already screwed.

Now remove the 17mm galley plug. Put teflon tape on the new plug and sensor, install and run your wires.

The rest is reverse order. Hope this helped and thanks for reading!
 
#13 ·
The purpose of this write up is to show the way I believe is best to install a oil pressure sensor. There are 3 most common places to put your sensor or sending unit.

1. In a oil filter sandwich adapter plate.
This is a plate with threaded holes in it for sensors, sending units, or plugs. It screws on where the oil filter does from the factory and then you screw your oil filter to that.

2. Rear galley plug.
This is simply a plug in the engine block that goes to a oil passage. It is located between the outlet of the turbocharger and the intercooler if your looking straight down at the engine.

3. Front galley plug.
This is the same as the rear but at the front of the engine just to the left of the alternator if your standing in front of the car. The only difference between this plug and the rear one is this one is threaded with a factory dummy light sensor in it.

I prefer using the front oil galley plug for my sensor/sending unit for a few reasons. One is because it is cheaper. The most you would have to buy extra to use this location is another plug with a different thread hole in it. I got a prosport one for $13 shipped. This is much cheaper than a sandwich adapter! A sandwich adapter also adds extra parts which raises the risk for a leak, can have clearance issues, and puts your oil filter a little closer to the ground. While there may not be much of a pressure difference I prefer the front galley plug because it is only inches from the oil pump. The oil passages branch off before they get to the rear galley plug so, this may cause a slight difference (probably not enough to make much if any difference) in pressure readings between the front and rear galley plug locations. My opinion is that the rear galley plug location is better than a sandwich adapter but, not as good as the front galley plug. With all that said you can make your own decision on where to mount your hardware. Now on to the install.
Do you know if the location above cylinder 3 is same thread as location under the alternator?
 
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