Early BMW OLM / Service Indicator 2

[B320i]

Since purchasing my vehicle nearly 3 years ago, I have been watching the BMW Service Indicator intently, with the overall plan of figuring out what makes the system "tick."

A quick recap so as you all know what I'm talking about:
- Prior to the introduction of "Long Life" oil in 1998, Special Oils (semi/fully synthetic) or mineral oils were in used up to 7,500miles interval.
- Once the LL98 standard came about, the interval increased to approximately 9,320 miles.
- Later vehicles, following the introduction of the 15K interval, supposedly make use of an in-sump OLM device, whose actual operation is questioned.

See Page 18

Theory on the early algorithm used by the SI2

The following intervals were before I measured the distance between each light extinguishing.
First Interval: 12,064km (7,496 miles) - "OIL SERVICE"
Second Interval: 11,865km (7,373 miles) - "INSPECTION"

For the 3rd interval, I ended up noting the distance between each of the 5 green lights disappearing at startup.
Service: 195,630km {121,558 miles} (i.e. 5/5 lights)
4/5: 198,301km (123,218 miles)
3/5: 200,536km (124,607 miles)
2/5: 202,750km (125,983 miles)
1/5: 205,105km (127,446 miles)

Serviced: 205,872km (127,922 miles), as one year elapsed since last service.
Bi-Annual Brake-Fluid/Coolant Reminder illuminated halfway through the interval with the "INSPECTION" lamp. Actual service was an intermediate "OIL SERVICE."

Actual Service Indication Estimated at:
208,895km
207,496km and
207,260km
(between 128,785 miles and 129,801 miles).

These figures were arrived at by creating a "mean distance between light extinguishing," and also used to calculate when the next green lamp would extinguish. This was accurate to about 100km (62miles) by the 1/5 point.

Now onto the next interval:
Serviced: 205,872km (127,922 miles)
4/5: 208,133km (129,327 miles)
3/5: 210,512km (130,806 miles)
2/5: TBA
1/5: TBA
Service:

I will continue to keep a tab on the Service Indicator, to see if there are any apparently trends in the typical interval recommended. At least in my case, the system has not been hugely variable, despite a shift from country, highway drives into far more short tripping in the city.

Yes, I probably have too much time on my hands. Quit looking at me like that!

 

[Quattro Pete]

What year is your BMW?

The OLM (if you can call it that) in my '02 is purely based on the amount of fuel consumed, 2375 liters to be exact. So each one of the 5 lights/dots is good for 475 liters.

 

[B320i]

Production 09/1993, per the sticker on my shock tower. So a 1993.

 

[djb]

You likely have the simple float based oil level sensor.

The later oil level monitor has a capacitive sensor. It's simply a narrow circuit board with two isolated strips. Some have claimed that it somehow monitors oil quality (really? by a change in dielectric characteristic? magic?). In my experience it isn't even reliable detecting a low oil level.

 

[UltrafanUK]

The OLM systems used by BMW are either based on fuel used or engine on time. They are very reliable.

I can't understand what the average OCI interval they recommend is, so perhaps some good person could figure it out ??

 

[B320i]

Originally Posted By: djb
You likely have the simple float based oil level sensor.

The later oil level monitor has a capacitive sensor. It's simply a narrow circuit board with two isolated strips. Some have claimed that it somehow monitors oil quality (really? by a change in dielectric characteristic? magic?). In my experience it isn't even reliable detecting a low oil level.

I have not noticed any sensors whilst futzing around under the car in the past, being the lowest trim level (a 320i), it has none of the fancy onboard computer stuff (low coolant, washer fluid, OAT etc) other models got. Of course, it could be there and I simply haven't found it

Have heard of the later conductive sensor used, and forum posts where people changed their oil and noted little to no difference in the OLM read-out.

Originally Posted By: UltraFanUK
The OLM systems used by BMW are either based on fuel used or engine on time. They are very reliable

Fuel or perhaps the "equation" in the thread linked. The documentation for this one more or less indicates a "variety of factors" influence the OCI aside from fuel usage, with the latter apparently being a better indicator - hence the switch to fuel usage later on.

Originally Posted By: UltraFanUK
I can't understand what the average OCI interval they recommend is, so perhaps some good person could figure it out ??

Exactly the purpose of this post

The stipulation that BMW Special Oils not be used longer than 15,000km/9,320 miles is a hint, to me. Near as I can tell, the switch to the longer 15K/9.32K interval was around '95 for the E36 and continued to that series end of production. I know for sure the E36 owned by "Doug's Domain" is on the later interval, early posts about the car around 1999 or so point to that.

I am unsure what happened with the 5 and 7 series, although I understand those received the well-known 15,000mile interval more around 1998/99 with LL98 oils. It could have been later.

 

[bmwpowere36m3]

My '98 M3 has the service indictor... I never use it, just reset it as necessary. I do oil changes are anywhere from 5-8k using HDEO or synthetic oils (5W-40, 15W-40). When I was taking my car to track days I changed it a little more often (but not after a single event).

I wouldn't run the M/S 50/52 engines on 15k intervals.... BMW also states the diff oil is lifetime as well as the transmission, yeah right!

 

[bmwpowere36m3]

Personally I'd feel comfortable running a good dino oil out to 5k and a synthetic to 10k OR 1 year (whichever comes first).

 

[andyd]

Every BMW E 28 made has a very accurate Low oil level sensor and a low coolant level sensor. Also a primitive OLM that can be rest with a paper clip.

 

[B320i]

Thread Update:

Now down to 2/5 lights remaining, took 2,325km (1,444mi) to go from 3/5 to 2/5. Estimates have me on-track for 11,600km (7,207mi) service interval.

Will soon be doing an intermediate OC, VANOS in particular is not happy with the 10w50 synthetic in at present. Will not effect the OCI, as this vehicle does not have a sump-based OLM system.
As its a low-spec 6cyl, no onboard-computer, hence no "low coolant / oil" warning, not that I've seen the latter in an E36.

 

[B320i]

Further update:

Now at 1/5 lights, this time taking 2,324km (1,444mi) to reach the current point. That should put the OLM at about 11,611km (7,214mi) for when the service reminder illuminates, based on the mean km between each light extinguishing.

The reason this latest update took so long: The car was parked up for 2 months whilst I was away.

 

[B320i]

Another Update:
The "Oil Service" alert was displayed yesterday evening, the interval for this light was 2,318km (1,440mi).

Overall, this produced a service interval of 11,607km (7,212mi), whereas my predictions based on averaging the average distance between each of the five indicator lights had me set to travel perhaps 2km further.

As of today, the vehicle has approximately 217,479km (135,135mi).
Did not carry out the intermediate oil change as I had expected; although the OCI will probably be reduced with the Valvoline Engine-Armour 15w40 that is going in.