Low Oil Pressure

[nisskid]

ok so im going through the thought lines, wondering whats wrong with my car. basically as of late i have had a low oil pressure problem, it really all started from a trip up the river which was on a highway sitting at 110ks. When i got up there i realised my dip stick was out and oil had been spurted out onto the engine bay. i checked the level after and it seemed to be fine. Anyway, on the way back i noticed the oil pressure would drop down to near 0 or on 0. so i pulled over, gave it a few revs and the needle lifted slightly off the bottom of the gauge which made me think that it wasnt the gauges fault.

anyway recently its been getting worse, always dropping randomly down to 0 and i believe i can feel the engine shuttering off the line and in general not as smooth when the needle is down the bottom. now i dont think im just tricking myself into thinking its running rough but i guess its possible.

In the morning it runs very rough, when i go around corners when the car has been running for less than a minute or 2 it looses power when i try to accelerate out of the corner. It also has a smell of unburnt fuel which hangs around until its been running for 10-20mins, but that may be completely different to this problem.

so its got me thinking, i really do believe its a oil problem, not a gauge problem but it seems to have enough oil still.

any suggestions would be great, cheers.

Edited February 9, 2007 by nisskid

[sinistaGTR]

ouch mate might be oil pump, or might be a piston or something let go, i know when mine blew i had low oil pressure

[DVS JEZ]

yeah do a compression test, is it burning oil(blue smoke)?

[CruiseLiner]

my guess is cracked piston ringland if the dipsticks blowing out and pressuring the sump, thats how my 26 died

any idea if its pumping oil out of the breather hoses excessively?

Edited February 9, 2007 by CruiseLiner

[RellikZephyr]

have you recently put on a catch can??

if you have a its connected wrong might be why it spat the dipstick out

RellikZephyr

[Cubes]

Sounds like it has a few non-related issues.

Have you pushed boost up without throwing it on a dyno to check afr's and ign is all ok?

Detonation kills pistons and bearings. Stuffed bearings = low oil pressure.

[nisskid]

ok a few answers, i rekon ive seen white smoke come out the back when ive reved it up, as noobish as it is i really havnt sussed that out much.

CruiseLiner: dont think so

RellikZephyr: nah no catch can.

Cubes: A:F's are a tad lean but not unsafe, this was done a while back.

i know its not to clear but u can kind of see them.

[mattymagoo22]

If you can source one get an oil pressure gauge hooked up to your engine, if you can't take it to a workshop that can and have you oil pressure checked!!!!!!!!

when was the last time the oil was changed, when the oil gets contaminated and needs a change you can often smell the fumes you're describing.

If it blew the dipstick out then there has been excess pressure in you crankcase and maybe some leaking seals which can cause even more problems.

Man get it checked sooner rather than later and hopefully save your self some cash.

cheers Matt.

[Cubes]

Your afr's WERE unsafe as they should not have been that lean at that power level.

Your fuel pump was failing. Its quite possible over the last few months it has got lazier resulting in even leaner AFR's. Your Tuner should have suggested to replace your fuel pump ASAP or prepare for a dead motor within the coming months!!!!!.

As a comparison.

~4-5years ago I had mine run up on the dyno with 12.5psi. It made 152rwkw and the afr's were around 12-12.2.

I was told the fuel pump is dying and I should replace it asap. So I did. AFR's instantly dipped in to the 10's, I pushed boost up to 1bar, dialed in another 2 degree's ignition advance and the car ran like that for some years before getting tired of the rb20 and dropping in the rb30.

EDIT: Yes.. 5years ago and it was run in 3rd.

[nisskid]

yeh fuel pump was f**ked, how can u tell that from the dyno? the A:F goes down as the revs go up.

it now has a 040 in it. im about to go to boostowrx to get it booked in, but i dont want them to charge me if theres nothing wrong.

[paulr33]

there is an idiot light for oil pressure to low

so if it was the case, it should come on

i would suggest a complete oil change

to ensure some good oil is in it

and that the right level is topped up

and get it checked by a mechanic asap

[Cubes]

yeh fuel pump was f**ked, how can u tell that from the dyno? the A:F goes down as the revs go up.

it now has a 040 in it. im about to go to boostowrx to get it booked in, but i dont want them to charge me if theres nothing wrong.

Unless you have aftermarket management at 150rwkw it should never be running so lean in the top end.

For example... Mine used to start off as yours did, high 13's then slowly dip down to flat 13 then drop sub 12's at high rpm.

Yours holding an almost flat line is an indication that the fuel pump is 'close' to failing. It should drop much much richer at high rpm which its not.

[mattymagoo22]

The so called 'idiot' light comes on at only 20kpa or less, usually when its too late if its even working in the first place in no way should you rely on that to check the oil pressure, only to tell you your screwed!

when the engine is at operating temp (oil is warmed) it should have at least 8-10 psi and as the revs come up a good rule of thumb is 10psi per 1000rpm I'm not sure of factory specs but if its less than that i'd be worried. On the other hand how gummed up is your motor? is your relief valve in the oil pump is it jammed causing oil pressure to go sky high??? You shouldn't trust the factory gauge in the dash.

i can't see that those AFR are bad on such a mild engine (150rwkw) but like you said if its stock they usually run alot richer than that. Just outta curiosity what do you read those AFRs to be cubes?

Main thing get it checked (oil pressure) any workshop can check it you don't have to go to a big name shop just to have it checked it may be the best 20-30 dollars you spend!

cheers matt.

Edited February 10, 2007 by mattymagoo22

[RB GUN]

Yeah Have a Compression test. Usually the 6th piston stuffs up. (Thats what happened to my RB20 B4) the 6th piston was cooked

Edited February 10, 2007 by MRPREZ

[Cubes]

i can't see that those AFR are bad on such a mild engine (150rwkw) but like you said if its stock they usually run alot richer than that. Just outta curiosity what do you read those AFRs to be cubes?

Those afr's are perfectly fine IF it were tuned for it. As its running the stock ecu (I assume as nothing has been said otherwise) its definitely way way too lean and is an indication of a failing fuel pump. Months later the fuel pump is only going to get worse and slowly lean out more and more.

I read the afr's as erm......... 11.75-12 at the end of the power run. Not as lean as I origionally thought but none the less still slightly too lean for a 'stock' r32 making 150rwkw.

Given a cold night or increase in boost and those afr's will most definitely be too lean and detonation will occur damaging pistons and bearings.

[nisskid]

The so called 'idiot' light comes on at only 20kpa or less, usually when its too late if its even working in the first place in no way should you rely on that to check the oil pressure, only to tell you your screwed!

when the engine is at operating temp (oil is warmed) it should have at least 8-10 psi and as the revs come up a good rule of thumb is 10psi per 1000rpm I'm not sure of factory specs but if its less than that i'd be worried. On the other hand how gummed up is your motor? is your relief valve in the oil pump is it jammed causing oil pressure to go sky high??? You shouldn't trust the factory gauge in the dash.

i can't see that those AFR are bad on such a mild engine (150rwkw) but like you said if its stock they usually run alot richer than that. Just outta curiosity what do you read those AFRs to be cubes?

Main thing get it checked (oil pressure) any workshop can check it you don't have to go to a big name shop just to have it checked it may be the best 20-30 dollars you spend!

cheers matt.

yeh shaun at boostworx said i should be safe until the light comes on, but id prefer not to wait till then.

8-10psi is about 400-500 mm of Hg right? mine sits on between 150 - 300 crusing in 5th, when accelerating it goes to 400+ but the main problem is idle and low rev stuff (even cruising in 5th) when it will just drop down to sit on the bottom.

actually now that i read ur post i think u mean x100mmHg not psi, yeh that is true, general rule is 100mmHg per thousand rpm.

Its booked into Boostworx to get oil pressure and compression tested. hope all goes well.

Unless you have aftermarket management at 150rwkw it should never be running so lean in the top end.

For example... Mine used to start off as yours did, high 13's then slowly dip down to flat 13 then drop sub 12's at high rpm.

Yours holding an almost flat line is an indication that the fuel pump is 'close' to failing. It should drop much much richer at high rpm which its not.

no A/M Ecu unit, but when i saw those A:F's i figured it had probably been remapped.

If the fuel pump was able to supply enough fuel at the top RPM then it shouldnt be the cause for leaning out at any lower revs, if it couldnt supply fuel anymore the A:F line should have flattened out or raised at some point. i cant see where it has done that, but it doesnt really matter cos either way u were right and it did need to be replaced a while after that dyno.

[Cubes]

no A/M Ecu unit, but when i saw those A:F's i figured it had probably been remapped.

If the fuel pump was able to supply enough fuel at the top RPM then it shouldnt be the cause for leaning out at any lower revs, if it couldnt supply fuel anymore the A:F line should have flattened out or raised at some point. i cant see where it has done that, but it doesnt really matter cos either way u were right and it did need to be replaced a while after that dyno.

The lean afr's in the low to early mid rpm is perfectly normal. Its exactly what my stock rb20 ecu did regardless of what pump it ran. Its the mid to top end that goes rich when the correct fueling is suppied.

It may be that the fuel pump was only just on the edge of shieting its self which is why the afr's are so 'perfect', given a month down the track you 'may' have started to see the top end afr's start to lean out more. Similiar to mine except mine was a little more gone and was starting to lean out by a 1/4 of a point in the last 500rpm.

If that makes sense.

I still run my stock intank pump and it is well and truley stuffed, it only just provides enough fuel for off boost work. I also run an external bosch pump so the internal acts as a lift pump so its never working hard.

I must pull it out one of these days. :S

[nisskid]

yeh i wouldnt mind seeing the A:F's now with the 040 in, i will find out soon when it gets remapped again but i suspect they will be the same as in that dyno, Turbo Tune (dont laugh) didnt seem to pick up anything at the time, it was only recently almost a year later that boostworx said i should look at changing it soon, to be honest i didnt feel it leaning out when i was boosting it hard (before i found out the pump was f**ked) but i was going to change it anyway to an 040.

[mattymagoo22]

not sure about the conversions from psi to inches of mercury i don't go off the gauge on my dash if thats what your using, I'm too used to the old measure. if youre going to drive it keep an eye on the oil level and baby it, that means NO BOOSTING!

And cubes yeah about the AFRs I thought that they weren't too bad I didn't think they were dangerous but its good to get some input on what is whats borderline and what dangerous from peoples experience

Cheers Matt.

[nisskid]

yeh they are certainly close to borderline, too close for my liking, like i said its gonna get remapped soon so they will be sorted out.