Electronic Oil Pressure Guage

[Negative Boost]

Hey, sorry i dont know what else to call an Oil pressure gauge thats not mechanical but electrical dosnt sound right to me. Anyways...

This guage came off our parts car and we didn't get the sender unit with it. Here's a picture of the guage.





With wiring am i correct to say that,
Yellow - Ground
Red with White trace - Ign 12v
Grey - Pressure Sender Unit

And those 2 wires coming out the bottom are for the light.

Is that correct?

Also, could i use the stock 7MGTE oil pressure sender or will i have to get an aftermarket unit to work with this guage?

Thanks
Sam

[TA-022]

wiring sounds right ... any - + markings at the wire points on the guage?

anyway its definatley signal / + / - and the lights + / -


as for sender ; it will depend on the working signal the guage requires.

im pretty sure the work off resistance. + pressure should reduce the resistance letting through a greater voltage creating a higher guage reading.

so in theory 0hms resistance should = max pressure and reverse signal (prob bout 100ohm) would be like 0 pressure.


i think itll be a case of see what a 7m is std then hook the guage up and see if it gives that reading???

[brett_celicacoupe]

youll be lucky if the resistance range is compatable between the toyota sender and the gauge you have.

furthermore, the 7m probly only has an idiot light, ie ON or OFF.

check the VDO catalogue and check their sender units, see if the resistance range is compatable.

if you want to find out the resistance range of the gauge then youll need a potentiometer and a multimeter.

hook the multimeter in parallel with the pot (use the inner pin and one of the outer pins). connect one pin to ground and one to the sender inout at the gauge. now you just need to record the effective resistance of the POT when the gauge has just moved off the bottom mark and then at FSD (full scale deflection), this is when its just stopped moving at the upper limit.

and those 2 measured values are the resistance range.

[spectral]

Looks like the cheap Speco units in Supercheap Auto. Brand new they are about $22 with sender (thats what I paid).

[peedman]

Yeah bottom two wires are the lights. You can actually pull that rubber thing out and ur light bulb is stuck to it. Ive got a spare one of these lying around but really, these supercrap gauges are often inaccurate so dont spend too much on a new sender.

[TA-022]

$22? not for electric me thinks not.

mechanical yes leccy no.

[Negative Boost]

Thanks guy for the help.

The guage has no markings on it so i assume its an Supercheap item then. I didn't even realise they sold cheap guages like these.
There's not even any -ve +ve markings on it but i'm pretty sure i know which is which.
Considering its just a supercheap item i think i'll try and make it work with the stock 7M sender (its not a ON/OFF switch, its a resistance thingy, whatever you call it). If that dosnt work i'll go and look for a sender or buy a decent guage. I only really want to be able to tell if im getting any oil pressure at all though so i dont mind if its a little bit out.

Thanks again, + rep to all
Sam

[spectral]

$22? not for electric me thinks not.

mechanical yes leccy no.

Thats what I paid

In fact, I paid more for the various brass fittings from Enzed/Pirtek to get the NPT threaded sender to fit at the same time as the factory pressure sensor in the head (BSPT threaded).

You can buy it in a 3 combo with a water temp and voltage for $45 or something.

Negative Boost: If it helps, the stock 3SGTE and 4AGE "sensors" are a switch. So they were unsuitable for running a gauge, just a warning light for the dash. I tried rigging it up to the Supercheap gauge on the 4AGE and as soon as I turned on the ignition, the gauge just went off the dial.

[takai]

Spectral: only the 20v 4AGE sensors are switches, the 16v (inc GZE) ones are actually sensors.

[Negative Boost]

Thanks Spectral, it all helps. I'll let you know how it goes with it hooked up the stock 7MGTE sender.

[TA-022]

yeah i did the triple combo in the 28 a while ago ... worked fine .. just changed for a more oem look is all.

[spectral]

Spectral: only the 20v 4AGE sensors are switches, the 16v (inc GZE) ones are actually sensors.

Ah, didn't realise that. Thanks Takai, I should be more specific with the actual engine I used to test