Ian Carr

If I have not started/driven my car in a couple of days (well really only 1 day if it cools down completely) When I start the car it read no oil pressure for 5-10 seconds then when it does get oil pressure I can hear the RPMs drop (like the engine is all of a sudden under more load).

Should I be horrified? I think so... convince me wrong..

wampir

I've got same problem. If I start car in the morning I've got no pressure for about 5 secs, but also it shows me that i have no brake fluid. After about 5 secs it's ok, but no dropping of rpm or anything. Had this before but it was for about 1-2 secs. Now it;s colder, i have a garage where it's not so warm.
Maybe anyone could explain this?

DDP

Just today, a bit cold. I started my car and it took a sec or two to build oil pressure. But then it took about 3 full seconds to built 5 bar. I have 10w40 in my car right now, dino oil. Fresh rebuild 3k miles ago. Not much to worry about. Why do you think they say 99% of engine wear is on startup?

DDP

Or was that 95%?

That's a number Chris White would have stored in his brain.

333pg333

From what I understand the startup isn't the worst time, it's once you've commenced driving and the car is under cold load. Anyway move to Australia and you won't have that problem. lol

DDP

You best not question me with my extensive racing experience.

Ski

Basically your oil system is loosing it's prime or you're having pick up issues.

wampir

Isn't this beacause of a bad oil and cold weather?

Spidey944

are you using an OE oil filter? the check valve in the OE oil filter is supposed to help prevent oil pressure loss after sitting for a few. All cars will have a slight lag in oil pressure build up, but 10 seconds seems a lil high.

Ski

Having just gone through this on a new build...and after trying all the easy tricks (re-torque front crank bolt, OPRV cleaned and changed o-rings several times, OPRV seated with factory tool and without, factory filters) it turned out to be the oil pump did not seal properly because of miscommunication between parts cleaner and installer, who put on the loctite 574.

SD Porsche Fan

Which oil filter are you using with what weight oil? Also check the connections to your oil pressure sensor. I had a loose connection that created erratic measurements.

eniac

When I saw the OP this was the first thing that came to mind. The OEM filter is one of the few on the market that has a check valve. It's the best filter to use unless your some insane crazy person with a dry sump.

I normally have 0 lag on oil pressure except on really cold mornings in can take a second or two.

User 41221

+1 on the oil filters. Seriously, guys, use Mahle OC-142 oil filters and stock paper air filters, change them (and your antifreeze coolant) at reasonable intervals, and your shortblock will last the life of the car.

Little known factoid here... those K&N air fliters everyone loves to install? They let a LOT more (and larger particles) dirt in your intake than the stoclk paper ones do, and they don't flow any more air. Bad news if you want to drive your car a long time.

Regards,

eniac

Please lets not start the stock vs. K&N air filter debate up again. Both types of airfilters have thier purpose and with PROPER use either is fine IF used in the conditions they were intended for.

M758

change the oil filter. I had a Mahle unit where the anti-drain back failed. It only happen once in 10 years of owner ship and lots of race car oil changes, but it can happen.