Nexsys oil pressure sensor kit

JohnDaviz

Lieutenant
Jan 6, 2019
903
621
0
Ride
335i E92 DCT
I looked into this further, this is normal operation and values above atmospheric pressure are correct. Pressure will read ambient until oil pressure exceeds ambient pressure. This is exactly how the system functions on the N/S55. Here's a log from my 2017 M2 where poel_w is the oil pressure. With the engine off oil pressure remains close to ambient, while cranking the pressure increases past ambient. If you are looking to use our kit to verify oil pressure is primed (after say a rebuild) then just ensure it increases while cranking (this applies to stock N/S55's as well since they operate in the same way). BMW states the minimum oil pressure for the N54 at idle (fully warmed up) is 1.5 bar or 21.75 psi and 4 - 6 bar at higher RPM (again, fully warmed up).
View attachment 77263
But it is reading 1 bar when the engine is off. And it is not reducing the 1 bar when reading at operating temp.

Or actual ambient pressure which may vary. It is no substracted as it should.

An oil pressure sensor is supposed to show absolute pressure. Most users will not know that ambient is not substracted.
 

bahn

Sergeant
Platinum Vendor
Nov 5, 2016
250
414
0
Iowa
But it is reading 1 bar when the engine is off. And it is not reducing the 1 bar when reading at operating temp.

Or actual ambient pressure which may vary. It is no substracted as it should.

An oil pressure sensor is supposed to show absolute pressure. Most users will not know that ambient is not substracted.
You dont need to subtract it, think of it as the maximum between ambient atmospheric pressure and oil pressure. Below is an example, idle with oil fully warmed up (very important as pressure changes greatly with oil temp). If this value needed ambient pressure subtracted then actual oil pressure would be 24.37 psi - 14.2 psi = 10.17 psi. Remember the minimum oil pressure at idle according to BMW is 1.5 bar or 21.75 psi and this engine is healthy.
1673467571712.png


Since the N/S55 works in the exact same way and has a sensor in stock form, lets look at it's limits and thresholds;
1673467932726.png

At 720 RPM & 223 F oil temperature the threshold for alerting is 1515 hPa (you have to perform bilinear interpolation). 1515 hPa = 21.97 psi which is pretty much identical to the N54 minimum oil pressure. There's a lot of people who have logged the N54 oil pressure through other means, typical hot oil idle is in the mid 20's, 24-28 psi and 65-80 psi at higher rpm. Which is exactly what we see on our kits.
 

Jern54

Sergeant
Oct 18, 2019
300
1
183
0
Netherlands
Ride
E91 N54 335i
It's a matter of what you used to work with.
In my industry (shipping) we are used to work with gauge pressures and in my opinion it is much more convenient to know than absolute pressure.

absolute%20gauge%20diagram.png
 

gmx

Specialist
Dec 8, 2017
69
29
0
Ride
BMW 1M
I received, installed, flashed. Works good.
What I must say is this sensor itself does not look genuine nor OEM. It's aftermarket as even in QTY < 10 you can get them for less than a tenner.
 

Asmo

Private
Aug 23, 2020
43
38
0
I think you guys are jumping to conclusions here on the licensing (especially calling it cartel & illegal). The licenses will be available separately they just aren't on my website yet. I was going to make them available independently for supporting a second hand market since MHD licenses are tied to the vehicle (hence why they are not on the website yet). I'm not sure why you'd want to use a different sensor though as you'll find it's hard to source one in the appropriate thread without using adapters. I guess some people like to spend more money in the long run than just buying the complete kit?
It's been a few months. Can we now buy the license separately? :)
 

JohnDaviz

Lieutenant
Jan 6, 2019
903
621
0
Ride
335i E92 DCT
Hey guys, Hey @bahn
a friend reported a weird minor issues.

He has Comfort Access if that is an important information. He gets into the car, puts the key into its place and starts the car as anyone does without comfort access. He then gets an active oil pressure light and sometimes a big oil pressure warning check control message for half a second and after that everything is fine.

Anyone else experienced that? Is that a known phenomenon?
 

Brule

Sergeant
Feb 20, 2017
379
452
0
Ride
335i 2007 6spd manual
Anyone have datalogs of a launch from a stand still of oil pressure?

How much does it drop?
 

E82_jester

Lurker
Jun 18, 2023
10
0
0
Minneapolis
Ride
2009 135i 6-speed
I just recently installed this oil pressure sensor kit on my car almost a week ago. I set my idle to 950rpm due to clutch chatter so idk if that’s why my readings are a bit higher. However at idle (oil cold) I’m seeing about 60-75psi. At idle with the oil up to temp I see 50-60psi. During moderate load I see with oil at temp I see anywhere from 80-100psi. During hard acceleration with oil at temp I’ve seen as high as 110psi for a second. Is this normal or should I be checking for issues?
 

DirtKurt

Corporal
Nov 5, 2016
179
196
0
NH
I just recently installed this oil pressure sensor kit on my car almost a week ago. I set my idle to 950rpm due to clutch chatter so idk if that’s why my readings are a bit higher. However at idle (oil cold) I’m seeing about 60-75psi. At idle with the oil up to temp I see 50-60psi. During moderate load I see with oil at temp I see anywhere from 80-100psi. During hard acceleration with oil at temp I’ve seen as high as 110psi for a second. Is this normal or should I be checking for issues?
I'll have to look at kine next time I go out, but from memory that sounds very similar to my readings with fresh 5w40
 

Carbonic135

New Member
Jul 28, 2023
2
6
0
It's been a few months. Can we now buy the license separately? :)
Pretty piss-poor response from Nexsys. After initially (December last year) agreeing to sell me just a Licence Austin simply quit responding to my emails. Here’s the reality check: I live in South Africa, so shipping a little bag of off-the-shelf hardware halfway across the world, and then incurring further duties and taxes is an expensive, DUMB idea! If you’re in the game of selling IP, don’t contaminate it with nickel and dime value adds.
 
  • Agree
  • Like
Reactions: kulixo and TiAgAu

Carbonic135

New Member
Jul 28, 2023
2
6
0
Pretty piss-poor response from Nexsys. After initially (December last year) agreeing to sell me just a Licence Austin simply quit responding to my emails. Here’s the reality check: I live in South Africa, so shipping a little bag of off-the-shelf hardware halfway across the world, and then incurring further duties and taxes is an expensive, DUMB idea! If you’re in the game of selling IP, don’t contaminate it with nickel and dime value adds.
Update: not sure if my post triggered a reaction, or if it was pure coincidence, but the Licence-only option was added to the Nexsys store shortly after I posted. Bought the Licence, bought an N55 oil pressure sensor, and a minor mod to a PDC plug saw me having all the hardware.
Deciphering the sensor pinouts was a bit of a challenge (got it wrong 1st time), but a pin swap and I’m IN BUSINESS! Really happy with this peace-of-mind upgrade. Licence fee is well worth the R&D value.