Help/Advice wiring oil pressure sender unit
Can someone give me some advice, I spotted this unit (see pic) in my engine by and to my understanding is the oil pressure sender unit which i have an oil pressure gauge so i thought i'd wiring it all up and hopefully it works 
So what do i need to do to the sender to get it working?
Is it just a case of connecting a piece of wire to the left of the sender unit?

So what do i need to do to the sender to get it working?
Is it just a case of connecting a piece of wire to the left of the sender unit?
Last edited by Jay-C; Dec 4, 2010 at 10:34 AM.
Can someone give me some advice, I spotted this unit (see pic) in my engine by and to my understanding is the oil pressure sender unit which i have an oil pressure gauge so i thought i'd wiring it all up and hopefully it works 
So what do i need to do to the sender to get it working?
Is it just a case of connecting a piece of wire to the left of the sender unit?


So what do i need to do to the sender to get it working?
Is it just a case of connecting a piece of wire to the left of the sender unit?

That's quite odd. It would APPEAR that a T-piece has been used from the taping above cylinder 3, into which are screwed a possible temperaturegauge sender AND what looks like the o/p switch?
If that's so, it begs 2 questions:
1. Why has whoever did it not left the o/p switch where it was?
2. And how do they expect to get a decent temperature reading on the end of a great long pipe like that?
If that's so, it begs 2 questions:
1. Why has whoever did it not left the o/p switch where it was?
2. And how do they expect to get a decent temperature reading on the end of a great long pipe like that?
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The side one looks like a std pressure sensor, but why is it connected via no.3 cylinder rather than its normal position under the alternator??
The top connector is for the aftermarket gauge.
A separate earth may also be needed for the extension body.
I must type faster next time
The top connector is for the aftermarket gauge.
A separate earth may also be needed for the extension body.
I must type faster next time
Last edited by Butty; Dec 4, 2010 at 01:17 PM. Reason: Doh- beaten to it
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Looks like who ever fitted it is running a oil temp switch and a oil pressure gauge from above No 3 cyl aswell as keeping the oil pressure switch in it's OE position. I fitted a oil pressure gauge, you will need to run a earth wire from the t-piece to a suitable earthpoint on the engine.
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Looking at the picture again that is not near cylinder three it's above cylinder 2 I think as it is on the passenger side of the vehicle. So it could be the OE pressure switch and a oil pressure sender.
Thats the exact same setup as what I'm running....
The bit on the left is the standard oil pressure sensor, that SHOULD be connected up to the car wiring loom (this puts the oil light on the dash)
The bit on the top is for an oil pressure guage, there should be a wire that goes from the top screw, and goes into your guage.
The bit on the left is the standard oil pressure sensor, that SHOULD be connected up to the car wiring loom (this puts the oil light on the dash)
The bit on the top is for an oil pressure guage, there should be a wire that goes from the top screw, and goes into your guage.
The previous owner maybe mounted the stock pressure sender, and a seperate presuure sender for a gauge ther, possibly to make room for a oiltemperature sensor which is fitted into the block at the position of the stock pressure sender.
With a hose like that you can only get good oil pressure info, as the end is closed a temperature sender fitted there would be giving false/innacurate readings.
However, by conjuring up this he has freed up the original gallery plug position under the alternator for a temp sender, which does work there is there is actual oil flow, instead of just a dead end.
A gauge is usually connected to the threaded portion on top, with a ground wire also located somewhere on the sender, or earthing via the gauge unit.
With a hose like that you can only get good oil pressure info, as the end is closed a temperature sender fitted there would be giving false/innacurate readings.
However, by conjuring up this he has freed up the original gallery plug position under the alternator for a temp sender, which does work there is there is actual oil flow, instead of just a dead end.
A gauge is usually connected to the threaded portion on top, with a ground wire also located somewhere on the sender, or earthing via the gauge unit.
ok thanks for the info guys!
So where can i find the standard oil pressure sensor plug to connect it back up?
(As my warning light is a MUST!)
Then i can start wiring up the oil pressure gauge as that is simple enough, i think the gauge has its own earth.
Would it still be a case of need to earth the oil pressure sender as i've read many need too?
So where can i find the standard oil pressure sensor plug to connect it back up?
(As my warning light is a MUST!)
Then i can start wiring up the oil pressure gauge as that is simple enough, i think the gauge has its own earth.
Would it still be a case of need to earth the oil pressure sender as i've read many need too?
Update :
I've had a proper look around and the long braided line does go onto the block above cyclinder 3 (I think), which then runs to a T-piece that has the oem pressure switch and a oil pressure sender (which is shown in my first post)
Ive managed to find the wiring for the oem pressure switch loose in the engine bay so im going to extend the wiring so i can connect that back up.
Then im going to run some wiring from the big oil sender (in the pic) to the oil pressure gauge on my A-pillar and hopefully all will be well
Cheers to all for the info!
I've had a proper look around and the long braided line does go onto the block above cyclinder 3 (I think), which then runs to a T-piece that has the oem pressure switch and a oil pressure sender (which is shown in my first post)
Ive managed to find the wiring for the oem pressure switch loose in the engine bay so im going to extend the wiring so i can connect that back up.
Then im going to run some wiring from the big oil sender (in the pic) to the oil pressure gauge on my A-pillar and hopefully all will be well

Cheers to all for the info!
Update :
I've had a proper look around and the long braided line does go onto the block above cyclinder 3 (I think), which then runs to a T-piece that has the oem pressure switch and a oil pressure sender (which is shown in my first post)
Ive managed to find the wiring for the oem pressure switch loose in the engine bay so im going to extend the wiring so i can connect that back up.
Then im going to run some wiring from the big oil sender (in the pic) to the oil pressure gauge on my A-pillar and hopefully all will be well
Cheers to all for the info!
I've had a proper look around and the long braided line does go onto the block above cyclinder 3 (I think), which then runs to a T-piece that has the oem pressure switch and a oil pressure sender (which is shown in my first post)
Ive managed to find the wiring for the oem pressure switch loose in the engine bay so im going to extend the wiring so i can connect that back up.
Then im going to run some wiring from the big oil sender (in the pic) to the oil pressure gauge on my A-pillar and hopefully all will be well

Cheers to all for the info!

Hope you get it all sorted
Maybe a temperature sender for an oil temperature gauge (as that is usually smaller in size, and fits there , whereas a bulkier pressure sender unit usually does not fit there directly.)
It should have been connected like my picture above... where it goes into the port below the alternator
Last edited by Jamz_; Dec 6, 2010 at 11:52 PM.
Update :
I have now extended wiring for the oem pressure sensor so i now have an oil light on start up which goes out
I have then tried to wiring the top of the sender unit to my oil pressure gauge on my a pillar but i have no reading
I have noticed that it looks like the gauge may need a pos and neg connection to it?? (Its not pos and neg for the backlight as the holder is missing for the bulb)
So is it a case of just wiring these 2 wires to get the gauge working?
I have now extended wiring for the oem pressure sensor so i now have an oil light on start up which goes out

I have then tried to wiring the top of the sender unit to my oil pressure gauge on my a pillar but i have no reading

I have noticed that it looks like the gauge may need a pos and neg connection to it?? (Its not pos and neg for the backlight as the holder is missing for the bulb)
So is it a case of just wiring these 2 wires to get the gauge working?
Yes, it might be, plus if you can get a bulb-holder and bulb, a wire for that from lighting live, it ought to use the same earth.
Stick a couple of temporary wires in direct to battery to check if it works. Saves you fekkin about to find it doesn't
Stick a couple of temporary wires in direct to battery to check if it works. Saves you fekkin about to find it doesn't
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