Jump to content

oil pressure sensor


lekonna
 Share

Recommended Posts

Hi,

didn't get an answer for my previous question and now its getting bit important:)

So i have an oil pressure sender that has the resistance range from 3-160Ohm ( 0-10bar). I've connected

it to an analog input and selected oil pressure and a calibration map. However in one of the discussion threads

here, ray hall recommends values ranging from 0-130ohm for the 0-10bar range for the same sensor, i wonder

if its just a mistake or is there something to this?

And just to confirm, i shouldn't need a pull-up resistor for this, vipec will take care of the math for me ?

Why i'm askin is that i finally got the wiring for the car (2jz-gte) and was trying to build oil pressure with the starter motor,

the oil sensor showed 0 and the oil pressure light wouldn't go off. took off the hoses that lead to my oil thermostat and they

were dry. Also took off the plug from the oil pump that is directly after the pump, and there was nothing there. Disassembled

the whole timing belt side of the engine (could not get the pump out since its 2jz and in the supra and removing the pump requires

dropping both oil pans) then seeded the oil pump through the pressure relief valve hole.

After this i dropped the timing belt back on and run the engine with the starter, the pressure showed still 0, though now i got

some oil out of the thermostat hose. I removed the turbo oil feed and it was dry, and didn't get any oil there by turning the engine

with the starter.

Tomorrow i'll check if the pump still pushes oil to the thermostat and if it does i will crank the engine, for this i would need to be

able to trust that the oil sensor shows correct values, since if even with the engine running there is no change in the pressure i will

have to kill the engine and change the pump.

Link to comment
Share on other sites

verified today that the pump is not moving any oil, so tore down the oil pans and removed the pump (fun with the engine still in the car). will buy a new pump from toyota and install that, though i think the oil pipe in the lower oil pan was only hand tight and since its a metal gasket i don't think it was making a proper seal, so most likely the pump was sucking in air through there.

i might rig a manual gauge to the cap with the 10mm hex on the pressure side of the oil pump to make sure its working this time ;) though would still like to know the correct setup for the vipec for the sensor.

Link to comment
Share on other sites

OK, so once you have fixed your physical oil pressure problem,

Run the engine and check your oil pressure.

If the pressure is still registering incorrectly, then,

Can you do a search of your sensor and get the scaling values required to setup your Calibration.

Can you direct me to Ray's post regarding the pressure sensor and the settings that you mention in your first post, so i can read it and determine what it refers too.

Another option is to fit an OIL PRESSURE sender that has known values and is in the default setup of the CAL.

OR,

As mentioned above fit a mechanical pressure guage "T'd" off with the electronic sensor,

Run the engine and cross reference the oil pressure from the mechanical guage and see waht voltage the electronic sensor is generating under the runtimes value list, create your own Cal.

Link to comment
Share on other sites

Can you direct me to Ray's post regarding the pressure sensor and the settings that you mention in your first post, so i can read it and determine what it refers too.

viewtopic.php?f=3&t=490&p=3469&hilit=oil+pressure#p3469

here is the topic, i think it might be just a mistake on the interpolation.

thanks for the help.

Link to comment
Share on other sites

It appears the stated resistance values are relavent to that particular pressure sensor.

You need to find the values for your sensor.

Try to get the values in OHMS then you need to select Cal 1, 2 or 3 to create a calibration for it.

Another way of testing if you cant get the relative info, you need a multimeter and an air compressor with adjustable regulator a piece of fuel hose, 2 hose clamps and an air gun/nozzle.

Fit the piece of hose to the pressure end of the sender (end with the oil hole) tighten with a hose clamp,fit the air nozzle into the opposite end of the hose and secure with a clamp.

Measure the resistance of the sender unit with no pressure applied.

This value will obviously represent 0 psi/Kpa.

Set regulator on the compressor to 10 psi,apply the 10 psi of air pressure to the sender and measure the resistance (ohms), record the value, this will be used for the 10 psi in your Calibration table.

Procede with the above all the way to the maximum that you wish to read,

EG: 120 psi

Or scale it all the way to the maximum value for that sender )preferred).

Link to comment
Share on other sites

It appears the stated resistance values are relavent to that particular pressure sensor.

can you clarify this a bit? It seems that the range of the sensor is the same as mine, 3-160 Ohm for 0-10bar.

however Ray sets up the cal table in increments of 13, with a step of 100kpa:

Input Units = Ohms

Output Units = KPa

Table Start = 0 KPa

Table Increments = 100KPa

Resistance values for table 0, 13, 26,39,52,65,78,91,104,117,130

The table would result in 130 Ohm at the 1000KPa row, which is different than what the sensor spec says.

Link to comment
Share on other sites

well despite changing the oil pump and all the o rings and the metal gasket in the oil pans the car wont build oil pressura and i think i fucked a main bearing while turning it with the starter engine. nice reward after 20h of changing the oil pump in place. this stuff is too motorsport sometimes. tomorrow i'll pull the whole engine out of the car and do a biopsy. won't put it back together before i find whats causing this for good ..

Link to comment
Share on other sites

well the engine is now running and building oil pressure.

though the pressure sensor on vipec still shows a flat 0. Can you guys provide an example wiring diagram of a resistive sensor such as this? I can double check my wiring to make sure i got it right.

Link to comment
Share on other sites

Is your sensor the same as the one in the link you have supplied in the earlier post.

If it has 2 terminals,

1 terminal will go to your input you have selected as oil pressure.

The second terminal needs to go to sensor ground.

If it has 3 terminals,

One terminal will NORMALLY be 5 volt ref and you will have the analogue input and sensor ground.

Not sure if this is the information you where asking for.

Link to comment
Share on other sites

Is your sensor the same as the one in the link you have supplied in the earlier post.

If it has 2 terminals,

1 terminal will go to your input you have selected as oil pressure.

The second terminal needs to go to sensor ground.

If it has 3 terminals,

One terminal will NORMALLY be 5 volt ref and you will have the analogue input and sensor ground.

Not sure if this is the information you where asking for.

Alright, had time to take a good look at this now, and to me it seems its a bug in Vipec. With the sensor connected to AN Volt 5, set as "oil pressure" and using cal 1, the Cal 1 map is filled with the values scott showed here. The number remains at 0, even if i unhook one of the connections to the sensor (resulting in infinite resistance) it still shows 0.

When i measure the sensor it is showing proper resistance values. When i connect the sensor to a 1k external pull-up to the +5V line and use it as GP input, i get values though with this setup my resolution is not good (0,689V for 10bar) didn't want to use a smaller pull-up since not sure how much amperage the +5V can provide.

Could you guys do a bench test at vipec with just a simple potentiometer between the AN input and ground and try to see if you can get it to work, to me it seems like the internal pull-up is not getting set when i select the oil pressure -> cal 1 scenario, there is no way for me to configure this either.

Link to comment
Share on other sites

Good morning,

What do you have you AN volt fault setting set as? If you breach the upper or lower limit and you have the fault setting at 0 it could explain why PCLink is showing 0.

I have tested the oil pressure setting here on my simulator and it seems to be working well. Can you send me your base-map and I can test it for you.

support@vi-pec.com

Scott

Link to comment
Share on other sites

Good morning,

What do you have you AN volt fault setting set as? If you breach the upper or lower limit and you have the fault setting at 0 it could explain why PCLink is showing 0.

I have tested the oil pressure setting here on my simulator and it seems to be working well. Can you send me your base-map and I can test it for you.

support@vi-pec.com

Scott

I've got:

AnV5 Error High: 5.0V

AnV5 Error Low: 0V

AnV5 Error Value: 850 Kpa

(changed the error value earlier to see if error gets trigged)

edit: map sent

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
 Share

×
×
  • Create New...