Oil Pressure Sender - then whats this?

[smokey]

with my limited understanding i was under the impression the oil pressure sender was located just infront of the oil filter

now when i went to plug in the connector i found this thing

could someone perhaps enlighten me? :1zhelp:

 

[Allan_MA70]

yeah thats it... your not going to run the stock oil cooler are you????

 

[smokey]

nah i've got a larger unit down there

i was confused because in pictures i've seen its just a little plug, not a big brass thing

 

[IJ.]

Smokey: It's usually a round cylinder about 35>40mm diameter with a single electrical connector in the centre.

 

[smokey]

i realise that from a picture someone posted on here and when i looked yesterday i was a little confused!

 

[IJ.]

LOL now you're a Mk3 owner !
(I'm confused daily)

 

[miggles]

Havnt you got a autometer oilpress gauge? If so then you need to hook your gauge up to that rather than the ecu one (that goes to your dash)

 

[bigal0043]

that is the oil pressure unit... the plug that goes into that should have a big boot on it... when mine fell off it took me a little bit to figure out how it plugged in but after realizing that the end of the plug slides onto the end... on the very end is a little ball the plug slides on there... its kinda hard to explain in words... but it dosent slide on like a normal plug but on the side

 

[DyslexicSquirrel]

i need to find mine... mine no worky

 

[Insidious Surmiser]

nah i've got a larger unit down there

i was confused because in pictures i've seen its just a little plug, not a big brass thing

the plug is the jdm unit (won't work w/ usdm gauges), the cylinder is the usdm unit

edit: maybee he's talking about the rubber cover?

 

[Big Wang Bandit]

I swapped mine out only to find my guage was bad. Swapped clusters and bam it worked again

Thanks Chris!

 

[89mkthree]

if you install an autometer gauge do you just replace the stock sender with the autometer one? is that ok with our ECU?

 

[bryanintexas]

if you install an autometer gauge do you just replace the stock sender with the autometer one? is that ok with our ECU?

I`d like to know this as well.

 

[SupraDerk]

I wouldn't think the ECU would be mad about it. Looking at the wiring diagram the signal comes FROM the ECU to the sender (which has variable resistance) which looks like it my be connected in parallel with the gauge. So as the resistance changes (probably due to the change in pressure of the oil) the amount of current flowing to the guage changes and drives the needle. So if you take away the signal you effectively create an open circuit where the oil pressure gauge is and it's like it's not even there.

But anyway, my guess is that the ECU would just keep giving out a signal, but the source voltage wouldn't go anywhere. Kind of like standing outside and screaming, but no one hears you. Don't take this for fact, just what I think is going on.

 

[89mkthree]

cool, can anybody confirm this?

 

[lazarous]

Having the sensor unhooked does nothing, When i would start my car the needle would shoot up, then go to zero and stay there no matter what. When i looked, the sender wasn't even hooked up. I hard wired mine, because the boot fell off

 

[3p141592654]

The oil pressure gauge is not a resistive type. It uses mechanical pulse modulation (check the TSRM for details). The ECU does use oil pressure as an input variable.

http://www.cygnusx1.net/supra/library/Wiring/pages/Page_048.html

 

[SupraDerk]

Notice it says "to oil pressure switch"...meaning it would be an output. And the gauge DOES have resistance.

http://www.cygnusx1.net/supra/library/TSRM/be/BE_043.html


It would seem to use a pulse to drive it, but either way, if you take away the signal from the ECU you have an open circuit across the gauge. And nothing would seem to be hurt by not running the ECU to the gauge.


Edit: And the sender is variable, but it looks to be a rheostat. It controls the amount of current flow, which I would assume would go into a capacitor and create the pulse.

 

[3p141592654]

Read step 3 "inspect sender gauge operation". Note how you use a light bulb and count the number of pulses. The sender is a switch that is pulse modulated depending on oil pressure. It is an INPUT to the ECU.

I quote: "the number of flashes should vary with engine speed",
There is no resistance spec on the sender (the unit that is attached to the oil pressure port on the block). It "sends' a signal to the gauge and ECU. Hence the name!

The receiver "dashboard" gauge has a resistance spec. It is a bimetal spring with a heater coil around it. It receives' the signal from the sender. Get it?

 

[SupraDerk]

If it's an input to the ECU then explain to me where the source voltage is coming from. Because the sender is grounded to the block and the gauge is relying on the ECU and sender. I agree the sender is an input to the gauge. But not the ECU.