Recently purchased a 99 Forster S... Just today coming into work during my 30 mile commute when the engine is below 1500rpm the oil pressure light goes off... Oil levels and temps are fine. Any thoughts? I've never experienced this type of problem in a vehicle before.
You may want to stop driving it, untill you can get a gauge on it and see what the pressure is actually at.
^^ good advice. Could be as simple as a bad oil pressure switch or could be some thing more in depth. Rather then throw a few options out there, rule out the switch first via a oil pressure gauge.
I'll look around the shop here for one. This is the oil pressure switch right? (I don't have any Subaru repair manuals, and I only know Honda engines and Ford Flat Heads.... I just fired her up and the light came on (as usual when you start) and then went off... So I don't know wtf is going on. Engine is still warm (1/4 way above cold). Please ignore my ignorance... haha
Thanks! I know I could go to the Honda dealership and buy the maintenance repair manual (thick ass book)... Can I do the same at Subaru or does anyone have a good source for this sort of literature? I don't mean the crummy Chilton books either
http://www.rs25.com/forums/f61/t73249-official-factory-service-manual-thread.html Lots of suby's are the same, so if you can't find your exact car there you might still be able to find what you need. Some of these more experienced folk could tell which other models that there are FSM's for in that thread had the same engine as the 99 Forester (not sure that the 99 RS was the same).
I believe you can order print copies from http://techinfo.subaru.com but the site appears to be down right now (might just be me)
So I haven't had time to mess with this yet, and I'm thinking I might as well replace the water pump and timing belt at the same time if I have to replace the oil pump...
I was reading on nasioc about this, at least similar symptoms, and some guys were saying could be as simple as a new pressure sensor or what happens often is the oil pick up tube gets cracked. That is a commom problem with subarus I guess. Not sure what motors they are saying its common for but your best bet is to check the pressure then go from there as stated previously. I am trying to find a pressure sensor that will trip at a higher psi than the stock one as a cheaper safety fail than buying a oil pressure guage. Not having any luck yet. So if anyone knows if such a thing exists let me know. Something above 5 psi perhaps but under probably 8-9 so that the light is not on at warm idle.
Warm idle is around 20-25 PSI (on the 2.5L turbo engines, at least). Just get an oil pressure gauge and call it a day .
It is most common on the 2.5L turbo engines. http://forums.nasioc.com/forums/showthread.php?t=1553337 I'm still not sure actually how common it is, but it does happen, and all the failures are virtually identical.
On the EJ257 engine, it just may be. On every other Subaru engine, that's probably not the case. I have only seen 1 pick-up tube crack, and Subaru covered the new engine. Your symptoms are more than likely caused by a faulty pressure switch, unless of course your oil is really low.
Long story short I think everyone agrees you need to test your oil pressure before you will know what direction to go.
Timely post. I just got my 96' Outback with 2.2 engine back from diagnostic. Makes a terrible noise (kinda grinding like slowly turning a box of nails) and much lifter wracket. Wrench says the oil pressure is low and erratic. Thinks my engine could be bad. However, he also said the oil pump could be not pumping enough but said replacement would still be close to $4-500.00 since its in a hard to get area. Question: is there a way to test the oil pump w/o diving off into it? I'm not much of a mechanic but I can do some things. Btw, motor has 210,000 miles on it. Thanks, pcwerk
Sorry to dredge this old post up, but are you saying the normal oil pressure is 20-25 psi? Thats close (23?) to what my wrench tested and claimed I had low pressure (on a 2.2 L Outback). I think I just read in a Chiltons that the pressure should be around 43 psi. Can someone verify which is correct? Thanks! pc
Not at hot idle. 20-25 psi is about right. Either the oil pump is pumping, or it is not. The pump cannot be anywhere in between due to its design. If the was an issue with the relief valve, it would be stuck open and you'd have no pressure.
Sorry to be so full of incorrect information, but it turns out that my oil pressure was around 8 psi! I guess I really shouldn't even be driving the vehicle at that low of OP? I was hoping it could hang in there until next Spring... pc
