Low Oil Pressure
 

so i just noticed it today that when i idle the oil gauge drops to almost 0 and the oil light comes on. when i start driving it barely gets to 30 psi. im about a 1000 away from a change so i dont know if thats the case. can it damage anything with low oil pressure?? also i pulled the stick and oil levels are fine on there..

if it helps my Z is an 06 and just passed 15k miles.

Oil pressure moves oil thorough the motor. You need oil pressure. Oil light ON means something is wrong. Have it looked at immediately.

If light is turning on that means its seeing zero oil pressure, do not drive the car at all! till you have it checked out.

I have reason to believe that if the oil level is normal and the motor has not grenaded itself and you've had time to post this on a couple of threads that it's the oil pressure sending unit. :icon44:

Let us know what the problem actually was!

I really doubt its the sending unit, usually there is a sending unit for the gauge, and a separate sensor for the light which only picks up if there is zero oil pressure. And for both to be failing, very very doubtful.

How often do you Change your oil? and How hard do you drive your Z? If all oil levels are fine but you are reading Low oil pressures then the cause is Motor Oil Breakdown. Get your oil changed regularly.

How many miles on the oil, and have you checked the level?

Do not drive the car at all.

I've looked through the parts site and the service manual, and I can only find one oil pressure sensor on the engine, so both the light and the gauge must get their input from it.

If you know something different, I'd like to see where you found the info.

I doubt the ECM uses a pressure sensor to monitor engine oil level. It might be a float or a flow switch.

I used to get 0 psi at idle. It occurs due to oil viscocity being low. Change your oil to an appropriate oil and check again. I use 0w40 for this reason..

The ECM does not monitor engine oil level. The only way to check your oil level is with the dip stick. Since the original poster's car is a 2006 model, I wouls suspect low oil level is the cause of the problem.

I suspect low oil as well. The other issue could very well be a bad sending unit. I also live in MA and we've had some pretty cold weather lately and the oil pressures at startup is super high, if you rev out the motor too hard when cold the pressure goes sky high and could blow out the sending unit.

In any case I would not drive it at all and get it looked at right away.

thanks for the replies everyone. i got it towed to a friends place and it was the sending unit. never thought it would go in 15,000 miles but thats what it was. so after a change and a new unit everything is good.

I have found little information in the factory service manual about operation of the oil pressure sensor. It IS the pressure sending unit. Unanswered question? Is the sensor also a relief valve?

Good news.

You would think Nissan would engineer a new sending unit that lasts 100,000 miles. It can not be that difficult.

I've got oil light last time then added a liter of oil and the light came off. I think I was low on oil since I can hear some ticking before I put some oil. My oil psi is on 60 upon start up and during operation it goes to 1/4. Is this normal?

Cold starts on the hottest days in south Georgia put my car's oil pressure over 100psi. The FSM says this:

Approximate discharge pressure (psi)
Idle speed More than 14
2,000 RPM More than 43
6,000 RPM More than 57

First off, I have a 2005 Touring Edition 350z with 45,000 miles.
I'm having a similar issue, on a hot California day (96 degrees) after the engine is nice and warm, I'm sitting right at 15 psi @ idle- no AC on. I raced a g35 for about a mile and then it dropped to about 10 psi @ idle- no AC on.
After the race I stopped in to pick up a pizza, about 5 mins. later I get back into my car start it up and it sits back @ 15 psi. I'm guessing the aggressive driving kicked it down.
My concern is about the 15 psi, I just purchased the car from a private party about a month ago and it wasn't having this issue. But right when I bought the car I changed the oil and oil filter- Mobile 1 full synthetic 5w 30. I looked back at the service records and it shows that they used 5w 30 but it doesn't say which brand.
I'm thinking of using 0w 40 next time to see if that helps but I just changed the oil and don't really want to drop another 40 bucks if I don't have to.

Let me know what you guys think. Thanks!

When you say the oil sending unit, are you referring to the oil pressure sensor on the bottom? I am having the same exact issue as you and my car is running fine, just had my oil changed 3 days ago but when I stop, pressure drops to zero, light comes on. I checked my oil dip stick and it is near the top of the checkered line??

You are replying to an 8 year old thread and probably won't hear from cmcurran5, who may no longer be here or still own his 350z after 8 years.

Answering your question... I have owned my 350z for 15 years. It was purchased new in 2003, and I had to replace my oil pressure sensor at about 80k miles when it stopped functioning: My gauge read zero when the oil level was correct. I did have the car towed fearing that the engine was "oil starved."