Electric Oil Pressure Gauge Problem

[Shiznit]

so i just installed an electric oil pressure gauge by prosport in my civic. the package came with the gauge and an oil pressure sender unit to tap into an 1/8npt plug. well the gauge install went well, when i turn my key to accessories the light shines a bright white, and when i turn my headlights on the light turns to amber like its supposed to. i tested it before i installed the sender unit and noticed that the gauge would spike to about 108 psi. i didnt think anything of it at the time.

then i went to install the sender unit. i used a sandwhich plate adapter that has 4x 1/8npt openings. i used silicon tape around the threads of the sender unit to prevent any leaks that may occur. on the sender unit the back side has 2 wire connectors. 1 is for a wire to a ground and the other is a wire that connects to the gauge itself. i connected both wires properly. finished my oil change and proceeded to check for any leaks which i did not find.

then i went to take my car for a drive to see my new gauges in all their glory, only to find that my pressure gauge is still spiking. i have a volt meter gauge, but im not exactly sure what im supposed to be looking for, since there is no power running to the sender unit that im aware of. im not exactly sure what the ground was for but i figured if there is a ground wire there should be a power wire. but i looked at the instructions again and it showed only 2 wires going from the back of the sender unit, the ground and the wire that connects to the gauge itself. so i figured that the sendor unit must send signals in volts through the wire that connects to the gauge. by that point i was too exhausted from the heat to work on my car anymore so i stopped. wtf is up?

CLIFF NOTES:
oil pressure gauge spikes when not hooked up to sender unit
oil pressure gauge spikes when hooked up to sender unit

 

[oc_civic]

some gauges should not be hooked given power when not hooked up because they may go too high and allter the setting... i had an electronic nitrous pressure gauge like that... i would just call the manufacture im sure its an easy thing to troubleshoot..

secondly you SHOULD mount the sending unit on the fire wall via braided line.. the vibrations COULD snap the sending unit off..

 

[Shiznit]

good looking out

 

[Shiznit]

quick question OC. how exactly is the sender unit getting power. i contacted prosport and they said that the cause is a poor ground or a wire that has a poor connection. what i cant figure out is why the sender unit has a ground wire.

 

[Matt.]

my auto meter sender unit has a power wire and a ground to it, not sure why yours doesn't/

 

[Shiznit]

nevermind i think i figured it out. the sender unit acts like a resistor so when pressure is low resistance to the ground is high and the gauge reads that as a low reading. when pressure is high resisteance is low and the gauge reads that as a high reading. the wire running from the gauge to the sender unit and from the sender unit to the ground is just one long ground wire with a variable resistor attached

 

[BseriesEG]

i got a electric autometer one and never got a sender unit yet. whats optimal oil pressure for a GSR? (never knew it exactly)anyone know where i can get one cheap? autometer is like over 50 bux just for the sending unit. where do they sell the braided line for it or is that somthing id have to make?

 

[Matt.]

i got a electric autometer one and never got a sender unit yet. whats optimal oil pressure for a GSR? (never knew it exactly)anyone know where i can get one cheap? autometer is like over 50 bux just for the sending unit. where do they sell the braided line for it or is that somthing id have to make?

you have an electric gauge with no sender????

Do you have an oil line running into the car?

 

[BseriesEG]

NO NO, no oil line running into my car lol, i got a autometer electric oil pressure gauge that i never hooked up yet . i was thinking about finally hooking it up. but i need to get a sender unit first and sandwhich plate. thats why i was asking about the other things. about the line and where to get a cheap sender unit. its not in the car yet. its just laying around collecting dust.

 

[Matt.]

NO NO, no oil line running into my car lol, i got a autometer electric oil pressure gauge that i never hooked up yet . i was thinking about finally hooking it up. but i need to get a sender unit first and sandwhich plate. thats why i was asking about the other things. about the line and where to get a cheap sender unit. its not in the car yet. its just laying around collecting dust.

did you buy it used? Brand new they come with a sender.

If you don't have a sender unit just hook it up to the stock signal.

 

[oc_civic]

did you buy it used? Brand new they come with a sender.

If you don't have a sender unit just hook it up to the stock signal.

i dont think that would work... its a universal gauge and NOT likely to be calibrated to the factory signal

 

[Shiznit]

you have to get an autometer sender unit. most electric oil pressure gauges only work with their respective sender units. try ebay for a used autometer sender unit or craigslist or your local car enthusiast forum.

heres an explanation of the procedure you should use to solve the problem i have that a local forum member told me to do

the psi in the sender creates a variance in the resistance of the grounding circuit and that is how the guage shows a reading. test for 12 (or maybe 5) volts at the wire going from the guage to the sender. If that's good, then do a current test (in line) over the ground wire with car running. it should fluxuate with differing oil psi. Or, you could do like i do, and get your money back and run a mechanical guage. Can't beat mechanical guages. P.S. the oil psi port on the block is NOT NPT. It's close, but you'll much it good that way. It's bpt (i think that's it. it's just metric pipe thread. Just an fyi)

 

[BseriesEG]

damn autometer prices. yea i got it used. i just need the sender unit