Subaru Outback Forums banner
1 - 18 of 18 Posts

·
Registered
gypsy danger: 07 outback 2.5i touring. often broken?
Joined
·
169 Posts
Discussion Starter · #1 ·
Is there anything that connects the oil pump and the timing belt/tensioner?

Replaced my belt today, when I got home the car was idling while I rechecked lvls, got in to turn it off, and low oil light was on. Didn't go away when I increased idle speed, but then flickered and went out a few seconds later... hasn't come back on with multiple restarts and more idling..

Is there any tests I can run besides buying a oil pressure gauge?

Car is a 07 2.5i with 218,000km on it.

Sent from my SM-G903W using Tapatalk
 

·
Registered
Joined
·
9 Posts
The pump is driven by the crankshaft ,, maybe the pump lost its prime somehow ,, did u replace any camshaft seals ,crankshaft seals etc?? If you have started several times and the oil pressure led stays off you should be good ,, try it again and rev it a few times , and watch to see if the oil pressure led comes on again.
 

·
Registered
Fresh Out of Outbacks!
Joined
·
14,499 Posts
Timing belt replacement doesn't touch anything on the pressurized oil loop, so this is most likely coincidental.

Some owners have found that the backing plate on the oil pump loosens up over time, and this will cause major reductions in pressure. Easy enough to re-seal for another 100k+ miles. Easier still if you do it in the middle of the timing belt job while everything is open.
 

·
Registered
gypsy danger: 07 outback 2.5i touring. often broken?
Joined
·
169 Posts
Discussion Starter · #4 ·
Good info. I had driven the car for mostly 30 min before I had the oil light come on, so I don't believe it's prime related.

Later the same day I noticed when I cycled the key the light did not illuminate when the engine was off. I grounded the wire from the sender to the block and it came on but it wasn't grounding through the sender. When I got where I was going I cycled the key, and the light functioned as normal.

I guess I will try a new sender. I can test pressure at idle while it's out anyways, but if its truly low, I guess I will be going back in to reseal the pump!
Thanks for the advice!.

Sent from my SM-G903W using Tapatalk
 

·
Registered
Joined
·
19,508 Posts
Following, with obvious interest. At this stage, the info does point to a faulty switch. (From what I've seen, the more common fail mode is "open" and no light, but a mechanical failure inside could lead to the switch sticking in either position. Took one apart a few years ago: http://www.subaruoutback.org/forums...22-oil-pressure-sensor-switch-how-clicks.html (Hope the photos show up. If not, it due to a Photobucket issue. Canbe overcome using one of several apps for browsers.)

Oil pressure measurements would be a great addition to the knowledge base here.
 

·
Registered
gypsy danger: 07 outback 2.5i touring. often broken?
Joined
·
169 Posts
Discussion Starter · #6 ·
I will try to get a reading soon. Unfortunately the car seems determined to stay home this week, started it this morning and it's sucking air into the power steering system.... ugh. So I have to figure that out after I get home..

Anyone know what size npt the oil pressure hole is?

Sent from my SM-G903W using Tapatalk
 

·
Registered
gypsy danger: 07 outback 2.5i touring. often broken?
Joined
·
169 Posts
Discussion Starter · #9 ·
1/8 bspt? Cool, anyone know of a adapter to not so I can put a gauge on It?

I did check the sender wire, it's not loose.

Sent from my SM-G903W using Tapatalk
 

·
Registered
gypsy danger: 07 outback 2.5i touring. often broken?
Joined
·
169 Posts
Discussion Starter · #10 ·
Finally got the bspt adapter. Oil pressure was about 18psi in neutral (800 ish) and 15 in drive (600ish rpm) i don't have a oil temp gauge, but I drove around for most of ten minutes before these measurements.

Is this normal/ Okay?

Sent from my SM-G903W using Tapatalk
 

·
Registered
2014 3.6R Limited
Joined
·
1,210 Posts
That sounds pretty low to me. I would expect at a minimum of 30 PSI at idle. I don't know Subie's spec's but I have never owned a car that had lower oil pressure than that at idle. What does the oil pressure do when you rev the motor?

Finally got the bspt adapter. Oil pressure was about 18psi in neutral (800 ish) and 15 in drive (600ish rpm) i don't have a oil temp gauge, but I drove around for most of ten minutes before these measurements.

Is this normal/ Okay?

Sent from my SM-G903W using Tapatalk
 

·
Registered
gypsy danger: 07 outback 2.5i touring. often broken?
Joined
·
169 Posts
Discussion Starter · #12 ·
Oil comes up quickly to about 90psi then seems to stay there.

How do most check oil pressure, after a long drive or install gauge and then try to warm up engine?


Sent from my SM-G903W using Tapatalk
 

·
Registered
2014 3.6R Limited
Joined
·
1,210 Posts
That tells me your oil pump is fine. Usually loss of Oil Pressure is due to main bearing wear. Does it have a deep rattle when you 1st crank it? Main bearings can do that when they are worn. I've seen old school V-8's live for a long time doing that!

Also Cold oil ='s higher oil pressure. Were you seeing 90PSI with hot or cold oil? Oil pressure spec's are certainly stated with a warmed up engine.

Oil comes up quickly to about 90psi then seems to stay there.

How do most check oil pressure, after a long drive or install gauge and then try to warm up engine? Oil pressure spec's are certainly with a warmed up engine.


Sent from my SM-G903W using Tapatalk
 

·
Registered
gypsy danger: 07 outback 2.5i touring. often broken?
Joined
·
169 Posts
Discussion Starter · #14 ·
All measurement done while engine was hot. There is a lot of rattles from the hear shields underneath, but they are light and "tinny" not deep.

Maybe I should go to a 40 weight for the summers?


Sent from my SM-G903W using Tapatalk
 

·
Registered
Joined
·
19,508 Posts
This thread might be helpful.

Your readings might not be bad. See attached from 2007 FSM.

The 07 has an oil temperature sensor; it's associated with the AVLS control system at the back of the right side head. Scanners that access the ssm data from the OBD connector should be able to display the oil temp. If using Romraider or FreeSSM, it should be one of the available PIDs. With BtSsm, it has to be programmed in.

My BtSsm full-time tablet dashboard includes coolant and oil temperatures. It takes noticeably longer for the oil temp to get up to 80 C than the coolant. The instrument panel temperature gauge can be at the normal position for some time before the oil temp starts to catch up.
 

Attachments

·
Registered
gypsy danger: 07 outback 2.5i touring. often broken?
Joined
·
169 Posts
Discussion Starter · #16 ·
Hey, that sounds better! I'm certain the oil was up to temp, car ran for ten min before and after I installed the gauge.

So Subaru says 14psi + and I got 15, sounds like I'm Okay? Not great, but still within spec no?

Has anyone done this test and gotten something similar to me?

Sent from my SM-G903W using Tapatalk
 

·
Registered
2005 OBXT Limited, VF37, STI intake, 5MT
Joined
·
1,610 Posts
15 at idle is about normal from the other AVLS (and AVCS) motors I've tested. Maybe a touch on the low side, but without using a certified gauge, there's usually a 1 psi +/- difference.

For reference, the oil pressure warning light doesn't kick on till about 5 psi or so.

After your drive, was the engine idling really low temporarily? The oil pump sucks at producing oil pressure below 500 RPM or so, and an ECU that hadn't had the idle relearned "by the book" after being disconnected can dip low after a drive before returning to normal. Usually, it's brief and the residual oil pressure doesn't pop the light.

You can also test the oil system "holding pressure" by unplugging the crank sensor and cranking the engine a few times. Usually, a system in good shape will take 1+ seconds for the oil light to come back on after cranking for several seconds.
 

·
Registered
gypsy danger: 07 outback 2.5i touring. often broken?
Joined
·
169 Posts
Discussion Starter · #18 ·
Bow that you mention it, yes. The idle was really low after I parked it. It was only for a second, after I came off the throttle each time. (Was trying to bleed the ps system)

I'm not 100% sure what caused the oil light, but I replaced the oil pressure switch after that, because it was NOT coming on at light check. Since then, everything seems normal.

Sent from my SM-G903W using Tapatalk
 
1 - 18 of 18 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top