Just picked up a 2008 350z with the vq35hr and it seems to pull very hard and runs good. But this is scaring me.

My idle oil pressure once it warms up is at this :


Now I am pretty retarded but I would say that is at like what. 8psi?
The oil pressure seems fine when driving. About 45 at 2500 rpm. Gets up past 90 too. I haven't opened the car up but I would guess it would have no issues hitting the 120 or over. So it seems fine once driving. But the idle pressure just seems bad to me.

Also my actual rpms are idling around 500 or so. Turn air on it kicks up to about 700 and the oil pressure does go up a little. But not very much more than that.

The following is with the air on blast



Going to throw a new filter and change the oil tonight and I will report back. I pray I don't have any serious problems on my hands here.

 

The pressure with a/c on is correct (15 psi), as the idle speed is also in the correct range. The 500 rpm idle speed is too low, and will cause the pressure to also be too low.

Mobil 1 0w40 with their M1-110 filter is a good combination and will help keep your pressure within range.

 

my 08 was the same way, never had any issue with it

 

I bought valvoline max life 10w40 synthetic to try. Is that ok?
So I should have nissan increase my idle? Or can I do it myself?

 

My DE was around that and I never had an issue.

 

I would not be recommended to increase the weight of the oil just use a good 5W-30.

If you want to correctly verify the oil pressure you will need to measure it with an actual gauge. The built in gauge is not known for being accurate.

As a side note the HR can have issues with internal oil gaskets that will reduce oil pressure but I haven't heard of problems with 350Z just infinities.

You can reset the idle your self by doing an idle air relearn but it will probably take you a few tries to get it to work.

 

Mine is the same. My buddys nismo is the same. He took his to dealer they hooked up mechanical guage and his min at idle 16 psi so within spec although his and my guage look exactly like yours.

 

That's how mine looks too. It's just an estimate. To get the real pressure you'd have to hook up a gauge.

 

Dont get too excited about any of the guages up their... They are not all that accurate.

 

Thanks guys gonna throw in a little heavier oil and do the idle relearn and hopefully be right on spot.

 

Good plan. If you get the idle speed corrected, your pressure will be within spec.

 

Looks way better now I changed my oil and filter. At about 25-27 after I let it warm up for about 10 mins.

Thanks guys

 

It will be the sama as before when the oil is actually at normal temp, which takes far more than 10 minutes. The FSM states HR idle speed as: A/T: 650 ± 50 rpm (in P or N position) M/T: 650 ± 50 rpm (in Neutral position.

 

Does it say what the oil pressure should be?

 

Yes. At idle speed >14 psi, and at 2,000 rpm >43 psi. Both are with oil temp at 176F. Those are HR numbers, don't have a DE manual, and I can only assume that's with the spec'd 5w/30 oil.

 

Maybe I was just low on oil then? There is a huge difference in pressure just changing the oil and filter. Even cold starting I'm much higher than before.

Doing the idle relearn sometime today. Will that correct my idle alone ? What actually causes it to lose the original idle ?

Thanks

 

Never had to play with that on my '08, now at 66K miles. My OBD2 scanner shows the warm idle speed at 675. Let us know the results.

 

Your oil gaskets inside the timing cover are blown. A near 10 hour job that requires removing the timing chain.

 

IMO, that's a stretch. Pressure looks fine to me.

 

Agreed, my oil pressure looked the same for awhile and my oil pressure light would actually come on at stop lights if my A/C wasn't on (and yes pressure was normal during any sort of acceleration or steady cruise), I did exactly what you did (and other things because my car was all sorts of goofed up), switched to heavier oil and the pressure will come back up but that fix is temporary. Sounds like those gaskets are partially blown just like mine were, I don't think it will cause any immediate problems, but unfortunately, you'll probably have to get those gaskets replaced at some point with the updated ones that are metal. Take it or leave it, just want to help.