Oil Pressure

[Gayle]

My oil pressure warning light comes on and stays on for a few seconds when I start the car. (the one that is shaped like an oil can. ) The word message would come on when I shut the car off. It is not low on oil. I thought it must be the sensor and that replaced. The word message hasn't been coming on when I shut the car off but the oil can light still seems to be there too long in the beginning and I think the word message is still there sometimes in the beginning. The oil can light is pretty consistent and the word message is intermittent.

When this problem first started a few months ago and I was trying to decide which set of lines the oil was supposed to be between, I very slightly overfilled it. That made the light go away. I had the oil changed the next week (please don't flame me that I didn't do it myself) and the problem came back.

I think I remember reading about a certain amount of oil is supposed to stay in the oil pump when you turn the engine off and if doesn't you get this oil pressure warning pattern. I also think I remember that it is a problem with the mounts and is expensive to fix.

Can anyone enlighten me? I know I am always telling people to do a search but do you have any idea how many threads come up in response to this search :(

I talked to my indy briefly when scheduling to take it in. He said yeah, his car was doing it do. Doesn't most of the engine wear happen in the first couple seconds it is running? Or did I dream that? Is this no big deal or should I be concerned?

[shogun]

The answer, you need a new 'ball'
http://www.e32fixes.com/results.asp?method=show_fix&fixid=5

[Gayle]

Thanks Erich

So how bad on the car is it that this has been going on for 6 months? It is never cold here at least.

[Morgenster]

My oil pressure warning light comes on and stays on for a few seconds when I start the car. (the one that is shaped like an oil can. )


Wasn't this supposed to be somewhat normal?
I thought oil pressure only gets to an acceptable level after a second or two on account of the oil pump just kicking in.
From what I've read it should worry you more if the light didn't come on at all.
I'm clueless about the message thing and so much more of course.

About the startup protection: Is it any good to use Castrol Magnatec synthetic to cover for this (other than being gentle with the car until warmed up)?

@Shogun: the fix you posted describes the symptoms to be there on shutdown, not startup. Is there a difference?

[Robin-535im]

Thanks Erich

So how bad on the car is it that this has been going on for 6 months? It is never cold here at least.
Here's one thing you can do that costs nothing: Park nose down. If you're on an incline, parking with the nose down keep more oil in the right place and the light goes off faster.

My first 535 did the same thing, and although I knew it was still broke, parking nose down made the light go off faster and I didn't worry about it so much. Considering the cannister is so expensive... I liked the cheap bandaid in this case.

[Gayle]

Wasn't this supposed to be somewhat normal?
I thought oil pressure only gets to an acceptable level after a second or two on account of the oil pump just kicking in.


That is sort of the question. How long is too long? The first six months I owned the car the oil pressure light went out quicker. It went out with all the other start up lights. Now it lingers. It doesn't linger that long, but it is a definite increase in how long it stays on.

[632 Regal]

shouldnt come on at all if the canister dont drain back. if the oil holds and stays then its solid pressure as soon as the engine is turned.

time to look into the canister, they should only be about $400.00 at the dealer.

[Gayle]

shouldnt come on at all if the canister dont drain back. if the oil holds and stays then its solid pressure as soon as the engine is turned.

time to look into the canister, they should only be about $400.00 at the dealer.

ouch

.

[632 Regal]

your the only one on here with money, me personally id try the shogun ball fixer.


ouch

.

[Bill R.]

normally the oil filter canister is always full of oil pumped up to it from the oil pump. There is a one way or check valve that always oil to pump up to it but won't let it drain back down,

So when you shut the engine off this check valve in the oil canister keeps the canister full of oil all the time , you start the engine after sitting all night and the canisters full already so oil gets up to the oil pressure sending unit and the rest of the motor right away and the oil light goes off.

When the check valve or one way valve goes bad then when you shut the car off for a long period of time , such as overnight, the oil slowly drains out of the canister back down the lines and into the crankcase, so now the canister is empty when you start the car in the morning and the light won't go off until the canister fills up completely then the oil goes to the pressure switch cam ,bearings etc.

This is a fairly common problem on the older m30, mine did it a few times when i was running 20w50 oil. My check valve is probably bad , When i switched to the bmw 5w30 synthetic and then switched again to the mobil ! 0w40 it doesn't do it since these oils don't thicken up as much when they are cold (cold meaning less than 100F).

The oil pump has a hard time sucking thick oil up to it from the pickup, once its at the pump then it can pump it under pressure , no problem but the suction side or pickup side of the pump is where it has a hard time picking up the cold thick oil. Using 0w40 mobil currently , it is much thinner when cold so it picks it up easily like drinking soda through a straw as opposed to drinking a really thick milkshake through a straw.

Since this oil is nice and pourable when cold its pulled up to the pump faster and the light blinks off quickly even if it drained down overnight. When you heat the oil up to operating temp it still a 40 weight thickness so you still get superior protection at higher temps but the lower viscosity or thickness when cold allows the pump to pump it easily and quickly .

Since i switched a few years back from 20w50 i haven't had any problems with it staying on a few seconds like it did before. 0w40 the light blinks off almost immediately, i have the valve cover off every couple of months and the cam lobes look fine , everything is still fine running 0w40 even in my high ambient temps year round.








My oil pressure warning light comes on and stays on for a few seconds when I start the car. (the one that is shaped like an oil can. ) The word message would come on when I shut the car off. It is not low on oil. I thought it must be the sensor and that replaced. The word message hasn't been coming on when I shut the car off but the oil can light still seems to be there too long in the beginning and I think the word message is still there sometimes in the beginning. The oil can light is pretty consistent and the word message is intermittent.

When this problem first started a few months ago and I was trying to decide which set of lines the oil was supposed to be between, I very slightly overfilled it. That made the light go away. I had the oil changed the next week (please don't flame me that I didn't do it myself) and the problem came back.

I think I remember reading about a certain amount of oil is supposed to stay in the oil pump when you turn the engine off and if doesn't you get this oil pressure warning pattern. I also think I remember that it is a problem with the mounts and is expensive to fix.

Can anyone enlighten me? I know I am always telling people to do a search but do you have any idea how many threads come up in response to this search :(

I talked to my indy briefly when scheduling to take it in. He said yeah, his car was doing it do. Doesn't most of the engine wear happen in the first couple seconds it is running? Or did I dream that? Is this no big deal or should I be concerned?

[ryan roopnarine]

as one of the techno-philes here, why don't you take a digital video of it and post it here so that someone can tell you if you have a problem or not.

[Bellicose Right Winger]

The only time I get the word message is on the first start after an oil & filter change. Seems like there's a time threshold must be exceeded w/o oil pressure to send the message. It can take 7 or 8 seconds to fill the oil filter housing after an oil change. I'd start simple and check to make sure the o-ring is installed at the bottom of the bolt that holds the oil filter lid on. This o-ring keeps oil from draining from filter housing to oil pan.

Paul Shovestul

[mamilapon]

The only time I get the word message is on the first start after an oil & filter change. Seems like there's a time threshold must be exceeded w/o oil pressure to send the message. It can take 7 or 8 seconds to fill the oil filter housing after an oil change. I'd start simple and check to make sure the o-ring is installed at the bottom of the bolt that holds the oil filter lid on. This o-ring keeps oil from draining from filter housing to oil pan.

Paul Shovestul
when I do an oil change, I put the new filter in and fill the canister with oil before putting the cover back on. Never even get the oil light at start up!!

[Gayle]

Short version, first define a few seconds. Exactly how many seconds is it


This morning I decided to study the time issue a little more carefully. Went out at started it in the garage just to see. Started counting using the "one thousand" equals one second method. The first start of the day was 3.5 to 4.0 seconds. The next was much shorter. I have a stop watch somewhere. Will try to find it and record times at all starts for 3-4 days.

[Dash01]

What about the pressure sensor? Did you say you'd already replaced that?

Some folks (including me) have had good results making the oil pressure indicator light stop going off by removing the pressure sensor and wiping it off, then re-installing it.

If that does not work, a new sensor is reportedly less than $15, and easy to replace. It sits at the upper rear of the engine block, easy to get at.

There is a good procedure on the 735i forums for checking and fixing the anti-drain valve in the oil filter housing, as related to us by Shogun.

[Bill R.]

sits overnight and cools down as cool as its going to get in SD anyway and its at its thickest and the canister where the filter is has emptied completely, First start of the day the oil is thicker and moving slower so it takes the 3,5 to 4.5 to fill the canister and get pressure up to the sending unit for the gauge,

You shut the engine after a half hour or so drive and the next start is say 2 hours later. The oil is still pretty hot at this time so its much thinner and pumps easily and quickly. Also the check valve in the canister isn't usually a fast leak so the canister doesn't usually drain entirely in a couple of hours

Easy cheap experiment, time the light on startup for a week or so everytime you start it, then switch to either a 0w40 mobil one or a 5w50 castrol synthetic and see how quickly the light goes out then.

If your car is anything like mine it will go out in less than a second, regardles of temp since it doesn't really get that cold here just like S.D.





Short version, first define a few seconds. Exactly how many seconds is it


This morning I decided to study the time issue a little more carefully. Went out at started it in the garage just to see. Started counting using the "one thousand" equals one second method. The first start of the day was 3.5 to 4.0 seconds. The next was much shorter. I have a stop watch somewhere. Will try to find it and record times at all starts for 3-4 days.

[Bellicose Right Winger]

Never see an oil light after oil change? Call me skeptical. Particularly on the M30 engine with it's inclined oil filter housing. This makes it impossible to completely fill not to mention that the oil is draining out of the housing while you're trying to fill it via the drain hole that's exposed when the oil filter bolt is removed. I gave up on this technique on my E34's. It was too messy on the M30 and I could never end up with anything close to a full oil filter housing. On my M50 the filter housing is much easier to fill, but like the M30 it drains too quickly make it useful.

Paul Shovestul





when I do an oil change, I put the new filter in and fill the canister with oil before putting the cover back on. Never even get the oil light at start up!!

[Morgenster]

Short version, first define a few seconds. Exactly how many seconds is it


This morning I decided to study the time issue a little more carefully. Went out at started it in the garage just to see. Started counting using the "one thousand" equals one second method. The first start of the day was 3.5 to 4.0 seconds. The next was much shorter. I have a stop watch somewhere. Will try to find it and record times at all starts for 3-4 days.

cold start this morning for me was 2 sec.

[Gayle]

Easy cheap experiment, time the light on startup for a week or so everytime you start it, then switch to either a 0w40 mobil one or a 5w50 castrol synthetic and see how quickly the light goes out then.


I will do the study the start up time part.

I have had discussions with the indy about synthetic. I know most people here think it is great, my indy made some compelling points about why I would not want to use it that were unrelated to the typical concern about causing leaks in waiting to become active leaks. At the moment not enough brain cells are awake yet for me to repeat those reasons. I will reconsider synthetic though.

[Ausmpower]

shouldnt come on at all if the canister dont drain back. if the oil holds and stays then its solid pressure as soon as the engine is turned.

time to look into the canister, they should only be about $400.00 at the dealer.

BOLLOCKS! The oil pump is empty when the engine first turns........plus the oil galleries in the head drain back overnight.

The light will always illuminate for half a sec when starting cold even with a full cannister, the oil has to flow upstairs to the head to switch the light off in a 535 (2 oil pressure switches on them, 1 for the DME, one for the idiot light)

An intermittant light at idle when the engine is hot is a concern not a second or two delay in it going off first thing in the morning..........

[Bill R.]

60 weight and its 32f outside then it drains down the bolthole so quickly that its useless to try and prefill. The only procedure i've seen from bmw thats different is on the spin on filter m20's, if it doesn't build pressure immediately they say to back the filter off 90 degrees and then start the engine and run until oil starts to leak out at the filter , then tighten filter back up.




Never see an oil light after oil change? Call me skeptical. Particularly on the M30 engine with it's inclined oil filter housing. This makes it impossible to completely fill not to mention that the oil is draining out of the housing while you're trying to fill it via the drain hole that's exposed when the oil filter bolt is removed. I gave up on this technique on my E34's. It was too messy on the M30 and I could never end up with anything close to a full oil filter housing. On my M50 the filter housing is much easier to fill, but like the M30 it drains too quickly make it useful.

Paul Shovestul

[Ross]

Sounds to me like it's draining back past the check ball shogun describes.
Easy enough to check. Pop the lid off the canister before the first start of the day. If it's empty you know it leaked back into the crankcase.
Three to four seconds is too long for the light to remain on.
If this isn't the problem it's time to examine why the pressure takes long to build up. Weak pump or internal leaks (banjo bolts?), worn bearings etc.

[Bill R.]

Bruno had this problem, and then Adnan had the same problem. It was determined that yes it is the check valve, but at the cost for a replacement housing from bmw it was prohibitive. Bruno ended up making an adapter plate and remote mounting a spin on oil filter on the fender well, the spin ons integrate a check valve and since his spin on hung down it stayed full all the time. He then attempted to sell the plate to others wanting to do the same but i don't think that very many people bought them from Bruno so i don't think he's producing any more of the adapters.

With this setup it was easy for him to add remote coolers as well since this was his track car at the time.

Adnan purchased a new factory housing for his and if i recall correctly it started acting up again less than a year later. A number of people tried disassembling the check valve as shown on shoguns page but all the check valves aren't the same, some aren't easily repaired.

For me when mine started having longer and longer intervals for the light to stay on when cold it was easiest to switch from the original 20w50 to 5w30 synthetic then recently i switched to 0w40 in the m30 so both my bmw's take the same oil now.

Adnan also replaced his oil pump i think trying to see if that elminated the problem. A number of other people have had this problem over the years on the board here.

Edit , as Paul S. also mentioned it can be the oring seal on the center bolt on the filter housing as well. Some of the cheesy aftermarket oil filters don't come with replacement orings for the center bolt, only for the cap.
Edit again, Here's Bruno's link on the oil canister
(http://www.bmwe34.net/e34main/trouble/OilCanister.htm) Most of the discussion on this was back around 2001 on Roadfly board




Sounds to me like it's draining back past the check ball shogun describes.
Easy enough to check. Pop the lid off the canister before the first start of the day. If it's empty you know it leaked back into the crankcase.
Three to four seconds is too long for the light to remain on.
If this isn't the problem it's time to examine why the pressure takes long to build up. Weak pump or internal leaks (banjo bolts?), worn bearings etc.

[BillionPa]

for less than a new canister you can get a high flow amsoil bypass system (if you have room in the engine bay) and start doing 20K mile changes!

[Gayle]

Edit again, Here's Bruno's link on the oil canister
(http://www.bmwe34.net/e34main/trouble/OilCanister.htm)

Thanks Bill. It means a lot to me to really understand the problem and understand my options. The visual was great.