At what psi does the oil light come on?

[Adrian87]

I'm starting to wonder if I am worrying so much about my oil for nothing..After being completely heat soaked, it reads 5psi, and I believe it's a mechanical guage. I have the GNX dash with VDO guages in it. It shows 80 on cold startup and my pressure throughout the RPM range is fine, but it's just sitting hot idling at a light that worries me. I just installed a new thrust plate and the blue spring on the oil pump, and that helped on the higher end, but not at idle. I'm thinking of going to 5w50. I have been running 10w40 Castrol Syntec. Any suggestions? I've not once seen the oil light come on even if the guage reads slightly less than 5psi so I'm wondering if it's off....any advice or input is greatly appreciated

 

[TS6]

I think it comes on about 4-6 psi. Could be the sender is disconnected for use with your gauge. I'd be worried if my oil psi was that low.

 

[turbo nasty]

In the summer.. real hot with a/c on in traffic in gear at idle. the oil psi w/ 20w50 is about 18-20 psi. probably a few psi lower w/ 10w40.

But i would not recommend that thin of oil in a turbo motor due to the heat in the summer.
The motor has protection when it hot as crap and that WS6 beside at the light is wanting some you don't have to worry.

 

[scgnx]

Was your oil pressure always this low or did it happen after you re-worked the oil pump ? Did you check the pump clearance ? Its absolutely critical for hot idle. I would suspect this may be the problem, having gone through the exact same thing last year. The gasket thickness between the plate and pump can be changed to both increase or decrease clearance.

 

[Adrian87]

Thanks for the replies. Should I go with 0w50 or 20w50? The first number is cold weight and the 2nd is hot weight, right? My pressure was about the same at idle before I put the plate in, it only seemed to improve it thru the rpm range and on the top end. Car shoots to 80 now when cold starting. The gaskets that came with the plate are really thin to begin with, I can't imagine a thinner one to increase pressure. (that's what I was hoping to do with the change) Where is the sensor for the oil light located? Is it just the oil pressure sending unit? Thanks again..

 

[TurboGN]

Adrian87, using the plate with the "onion skin" gasket, should help to give quicker pressure at startup but won't necessarily improve pressure. Especially if bearing clearances are off. Have you tried replacing main and rod bearings? Many see over 20 psi initially than settle down to the mid/upper teens after the thrust breaks in (without HV pump) with 20w30. This is after cruising down the highway then idling with the AC on high for several minutes. If you do this, change the filter often or until the gold dust is gone. Don't forget, the manual recommends retorquing the mains once. The rods should be shimmed while torquing. Good luck, Joel