NismoPick

So I got my 280zxt inspected today (let me remind everyone that it just got a motor rebuild... 2 miles on it before today) and it passed w/ flying colors. So I took it for a 10 mile drive on the freeway & as my coolant held steady right in the middle of the gauge (~180-190 degrees) my oil temp continued to rise. This same issue happened when my Z died coming back from MSA 07.

Anyway... the oil temp gauge has several markings on it (160* on the left, 300* on the right, and 4 non-marked lines in between). Before the MSA trip, the temp never got past the first mark (about 210*). Today the temp was well to the right of the middle mark, so I was calculating my oil temp to be somewhere around 250-260 degrees (WAY TO HIGH FOR CONVENTIONAL OIL ON AN EASY GOING FREEWAY DRIVE @ 70MPH, OUTSIDE TEMP ~70* AND I HAVE AN OIL COOLER) all the while my coolant is staying nice & cool. I get home, and use my infrared digital thermometer to check the bottom of the oil pan (right where the temp sensor is) and reads 210 degrees... right about where it should be. So either this brand new oil temp sensor is faulty AND doing the same thing the old one was, or my oil temp gauge isn't accurate...

I'll do an OHM check tomorrow on the sensor...

sho_shane

If it makes you happy my oil temp does not work at all

PurePontiacKid

If it makes you happier, I don't have one at all :P

BlueKitsune

I myself would take it out, boil up some water and drop it in and measure the temp manually then look at the gauge see if there's a diff

NismoPick

I like it!

snwbrderphat540

why even bother taking it out! you can just straight up pour the water down into the oil! think of how much time you'll save!!!!!!

BlueKitsune

{sarcasm} OH that that sounds great why not do that! {/sarcasm} lol

As far as I know the boiling water is the best measurement for temp gauges/senders to see how accurate it is.

SHADY280

hows the pressure read when the temp is going up?? it should loose pressure if its truely getting hot. me thinks you need to switch brands sender and guage, or at least style. are the wires getting pinched somewhere???

sho_shane

Cant you just delete that gauge? Go with something aftermarket?

NismoPick

Oil pressure was fine, and good call on the pinched wire... that could def have an effect on the resistance put out. I know that wire is dirty & brittle... I may cut it back to the harness & run a new one.

I can... but I'd rather get the stock one working correctly.

NismoPick

So I tested two brand new oil temp sensors... both registered well above where they should be. So I checked the wire... looked a bit crispy, cut it back to the main harness & soldered in a clean wire... same thing!

When the water was between 190* - 150* the temp gauge still hung in the middle (beyond 160*). I asked Bleach what his gauge does... never gets past 1/3. Anyone else?

straight hate

Thats why I don't run an oil temp gauge, lol. Seriously though, did you check for continuity between the gauge and sensor. You might have some corrosion build up in the harness thats screwing with the resistance.

snwbrderphat540

i say go aftermarket, good quality, replace the whole thing. its just old and probably fubar'd where its not even worth dickin with

BlueKitsune

First thing first, Holy crap your car is clean! second I agree with the corrosion idea I wonder if you can run a new wire all the way to the gauge