2.7 Low Oil Pressure

[Balisong]

Hello all. This is a very low mile 2.7 that was rebuilt and resealed on due to oil leaks from age. It was rebuilt by a reputable shop and received the typical 2.7 updates that you would want (case serts, Carrera tensioners, etc).

4K miles later and about 4 years, I am seeing an oil pressure problem.
I changed the oil and filter (china Mahle filter) and 20/50 Valvoline VR1.
Upon first drive after oil change is when I noticed the issue….green oil light illuminated. That alerted me to pressure gauge showing low pressure.
Pulled over and checked oil level and it’s correct and no obvious leaks.
Engine temp was fine.
Oil level gauge is showing accurate but notice how it doesn’t go down when car is at 3K RPM. The concern is that it’s not moving oil from tank to engine. Pressure gauge not really moving.
Video:
https://youtu.be/8mp_XvkWR0k?si=hQO3r_zVpWOI4Kmw

Did a visual inspection and found kinked hose going to oil tank.


Checked with hose vendor who advised me to reposition the hose to remove the kink. However other posters on the forum have said that hose is simply made too long and some have cut it and shortened it. I did reposition it and the kink has greatly improved and may go away after a few heat cycles, but no change in low oil pressure situation.

I pulled wire off of pressure gauge sender and it pegged the gauge which is the expected behavior. I presume it means the gauge is ok.

I don’t have a handheld oil pressure gauge but perhaps a next step is to order one. I’m concerned since I have the intermittent green oil light and low pressure on the gauge that I really do have a low oil pressure problem. The car won’t be driven until I figure this out.

Undercarriage photo:


Engine running video:
https://youtu.be/_CNWYDP-HvM?si=MEC7Ue62OD6wsO9l

Appreciate advice for next steps.
Thank you!

[EC900]

When engine is at 180°…I would (and did) add a little more engine oil, closer to the top hash mark on the dipstick and observe again, until satisfied with gauge reading. + Initially it’s best to add required amount and to be at the low end to be safe.
According to the manual the level has 2.64 qt difference between the lower and upper hash marks.
Don’t overfill.
Considering the sender and gauge are correct.
(Photos are from owners manual for reference)

[Balisong]

Thank you. But given the oil level is above the half way mark (on the gauge and the dipstick) my oil pressure should be higher and it should fluctuate with rpm, and the green oil light should not be coming on intermittently.
Do you agree?

[proporsche]

do you have to the right camshaft oil line this oil press sending unit-if yes that could be your culprit..If you disconnect and ground the wire the needle should peg to the top on the inside gauge.To replace it remove from the engine after put the block into wise and replace the unit..
If you try to replace it on the engine this could happen-the JB weld is absolutely no fix..just got this engine in, I have to take it apart and hopefully have it repaired or new case...
The oil p.unit is on the top

[BoxsterGT]

It was commonplace for the 2.7 motors to show low oil pressure after many miles from new. "Rebuilds" seldom correct all the tolerance & wear issues.

If you want to confirm the low pressure readings try a mechanical gauge. I doubt if the readings will improve.

Change your oil to a heavier grade like straight 30 or even straight 40.

For the Hose issue, a temporary fix is to loosen the cross under pipe where it is fixed to the motor so the kink will relax a bit.

You can also put a clamp around the kink so the hose becomes more round.

As soon as you are able, replace that Oil Hose with a correct one.

Even Porsche gets these hoses from vendors who are making them wrong.

Look up "out of spec oil lines" or "Oil Tank Hose".

Good luck.

Len

[Balisong]

Thanks for the info. There are some videos in my post that show how the gauge isn’t moving during acceleration. Also there is a video of the engine bay that shows the sender and tensioner setup.
Thank you!

[MrBonus]

That video looks like it could be a gauge issue.

[Balisong]

I’d love that. I did test the gauge by removing the lead from the pressure sender. The gauge pegged to the top like it’s supposed to.
The car runs and sounds fine so I’d like to hope it’s just the sender or gauge. The concern is the green light also illuminates intermittently (at idle) so that’s a second indicator of a pressure issue.

[proporsche]

Originally Posted by Balisong

I’d love that. I did test the gauge by removing the lead from the pressure sender. The gauge pegged to the top like it’s supposed to.
The car runs and sounds fine so I’d like to hope it’s just the sender or gauge. The concern is the green light also illuminates intermittently (at idle) so that’s a second indicator of a pressure issue.

yes there is;-)
did not see that one
so replace the oil press.unit....plus look on top of the engine with a mirror .There is a way to replace the -Idiot light- oil press.switch.....

I can give yo some write-ups about it..Just start with front one for now

Ivan

[Balisong]

Meant to post my triangle of death photo.

[mb911]

My 2.4 (same basic setup as yours) has similar mileage as yours great oil pressure but warm idle it’s a little low but no lights. That’s kinked hose is rough and makes me Kringe thinking about it.

[fanaudical]

You shouldn't be seeing an oil pressure problem after 4k miles after rebuild. Couple of questions:

Oil pump rebuilt / replaced / or just re-used?

Oil bypass mod done during the rebuild?

Later-model cam oil restrictors installed?

Any records of all the bearing clearances?

The oil pressure light is independent of the oil gauge. It's worth testing both. Absolutely get a mechanical gauge and install as a test.

[Balisong]

Thank you
It was an 11K mile engine.
Engine work was done before I purchased the car.
I don’t see any mention of the oil pump.
Says case was checked for bypass mod.
Not sure about restrictors
New bearings but no recorded clearance.

[Balisong]

Wanted to ask for recommendations on a mechanical pressure gauge with the correct fittings.
Thanks

[EC900]

Was that kink in the hose there for 4k miles of driving and never observed any low pressure or green warning light ?
I’m kind of reading that this was a gradual observation (?) of low pressure and you sought to change the oil to get a reasonable oil pressure. (?)

If this issue just occurred it seems the pressure drop was After the oil change and why I suspect oil quantity 10.5 qt initial refill may be low, and type of oil or viscosity when hot.

Did you change oil or someone else? Anything unusual in the old oil? Is it possible the sender is just clogged, all things considered that the engine was proper and is running fine… and sender unit is correct for the engine.

No leaks, no oil burning, but there is a normal oil consumption of up to 1/2 qt per 4k miles.

That is one clean engine. Hope you get the issue sorted.

[nickelplated5s]

I don't know if that is the supply side or return line but that's where to start. Any decent local hydro shop can save the ends and fab a new one.

[Balisong]

Thank you. Yes I would say I’ve never seen the green light until this oil change. I do not know how long the hose was kinked.
I have done all the oil changes and I’m pretty surgical and careful about it. I did not remove the sump plate. There was a minor amount of shavings on the engine and tank plug magnets. Very minor.
I’ll go ahead and top off the oil capacity, but I think given it’s at 3/4 full the car should show pressure and what concerns me the most is the pressure not changing as the car revs (video).
So I’ll top it off but I do think I should get a mechanical gauge and check it. Any suggestions on what to buy appreciated.

[proporsche]

have you consider just fixing the oil pressure problem???as i mentioned you should replace the oil sending unit.....
Ivan

[nickelplated5s]

Bali, calm down and replace the kinked oil line. My advice is do not drive it. Sensors, etc. next. I couldn't even take a shower with that line in my bathroom.

[ddinham]

I have this mechanical pressure gauge that you can borrow if it will help diagnose your motor?