Ok, a while back we had discussion involving the programing of the oil pumps keeping oil pressure down until the oil/engine temperature reached a certain level.
This discussion was in reference to cold start rattle and the possibility that this programing might be contributing to this cold start rattle.
My 2013 Mini Cooper ( with less than 8K miles on it ) has developed a noticeable cold star rattle when ambient temperatures were below freezing.
Well now that the ambient temperatures are now in the 90's the cold start rattle has completely disappeared.
My thinking is that this temperature sensor is increasing the oil pressure at start up when temperatures are high enough resulting in the timing chain tensioner putting more tension on the chain and reducing the cold start rattle.
Does anyone out there have any ideas on how one could fool the temperature sensor into thinking the oil temperatures are higher than what they actually are in order for the programing to increase initial start up oil pressure during cold weather?

 

Ok, let me approach this from a different level.
Are there any Mini Cooper owners living in colder climates who use something to keep their engines warm for start up during extreme cold weather?

 

my 2012 cms all4 runs the oil pressure at what I think is an alarmingly high pressure when cold
90+ psi at idle, up to 120 psi above 2000 rpm if the oil temp is below 45F!

I do not touch the gas until I have 45F oil temp when the pressure drops to a resonance value, under 50 psi

monitoring with scan gauge 2

 

I have about the same numbers on my 2013 R55s.

I make sure to NOT go above 2K RPM until the pressure starts to drop a little... It does get crazy high when its cold out.. which... is what most oil pumps will do... so Im not sure if its programming.. or just the factors of how cold oil flows..

But it does seem to drop rapidly once its warmed up.

 

I wonder if many of the oil leak problems are related to the high oil pressures when cold

 

I'm sorry, I misrepresented my original post by stating oil pressure instead of oil flow.
The oil pumps are programed to limit oil flow until after the oil reaches a predetermined temperature, which I would suppose increases oil pump backpressure if restricting the pumps oil flow.
I suspect the pressure readings you are getting is reflecting that backpressure as the pumps flow is being restricted.
The reasoning Mini Cooper's engineers used for this was to get oil temperatures up as quickly as possible to improve emissions and gas mileage.
Here's a link that explains this along with other engine functions.
http://www.motoringfile.com/2004/12/...nge_in_detail/

 

I disagree, the pressure sensor is located on the filter housing, past the pump so it is reading oil gallery pressure

#9 in the diagram

 

Valid point.
But why, if the oil pump is limiting oil flow at cold start up would oil pressure be higher at a time when flow is less?

 

Oil is thicker when cold...thigh not THAT MUCH WITH SYENTHIC...
So psi readis higher....
If you believe this is your issue...
Try a 0w-40 oil....
In all honesty, I doubt you will see much of a change from a 5w30 oil.....
The stuff pours and close great...not much difference between freezing temps and room temps...and that is your winter to summer argument....

Pumping less oil improves mpg...cold parts don't need as much oil to cool them as hot parts...remember, oil lubes AND COOLS...

 

I do an oil/filter change half way between the "free" included changes ...

mini uses 5w30 and I use mobile 0W40

I see no difference in oil pressure between the two

 

I use Mobile 1 0W-40 oil so it really should not be that sensitive to colder climates. In addition, I've never had a car that made this cold start noise winter time or otherwise which leads me to believe that the problem is more specific to this particular engine design than anything else.
My 2013 Mini is not a turbo model or with direct injection so it should not sound like a diesel on cold start.
Currently with ambient temperatures running in the 90+ deg. the engine is quite as a mouse on cold start up and sounds like a smooth running sewing machine.
But when ambient temperatures start getting below the 45 deg. the engine gets very noisy with the noise coming from the timing chain on cold start and lasts for 15 minuets until the engine has had ample time to warm up.
So it is obvious that temperature is the key ingredient in the cause of this problem and the why seems to posibly evolve around the oil pump programing to restrict flow at lower temperatures.
I absolutely hate it when it makes all that racket on cold start in the winter but it is not reasonable to only drive the car during summer months only.
I have no doubt that when the timing chain is rattling like this it is not doing it any good and if I don't find a solution it will eventually lead to a timing chain failure.
Thus my continued questions looking for cause and possible solutions.
If oil pump flow is being restricted until the oil warms up and is affecting the timing chain tensioner, what an be done to alleviate this?
If the oil pump's programed oil flow restriction in order to raise temperatures is not what is causing my wintertime cold start timing chain rattle than what is.
Even though I'm using 0W-40 synthetic oil, it is very much apparent that oil temperature or engine temperature a whole is a player in this as it only occurs in colder ambient temperatures.
Do they make an engine heater that would work in the Mini Cooper that would pre-heat the engine above the 45 deg. mark during the winter months?

 

my n18 turbo does not sound any different on a cold (oil temp below 45F) start, it just exhibits very high oil pressure until oil temp gets above 45F ... water temp does not seem to be a factor only oil temp

 

heres to digging up old threads. I have a bunch of questions about how the flow is controlled. my 2013 N16 has a solenoid in the oil pump. various postings on forums and phone calls to seven dealers have produced zero results. is the oil flow control solenoid a basic on/off, or high/low? if so what is the default setting? or is it variable flow by applied voltage? Im dropping this N16 into a 2007 that had a blown N12. if the default is full flow, Im thinking I can just ignore the oil pump solenoid and all should be well. hard to believe this has not been tried as N12s around here are stupid expensive.

 

I have always lived in cold climates and what we do when it gets very cold over night is we plug in an oil pan magnet to the oil pan overnight and unplug it after we get the vehicles started. We find it very inexpensive and it keeps the oil temperature warm enough as to not put undo pressure on our engines. Sometimes simple is better.

 

Not...rocket science...

I would have figured that ALL those that live in colder climates would have had this bit of knowledge passed down from parent to child at the appropriate time.
Yes...you can buy both block heaters (water) and oil heaters.

The block heaters are either a stick on pad or a replacement core plug that have a heating element within.

The pan(oil) heaters are a stock on pad to heat the oil to a given temperature.

I just did two quick searches for oil and water. MANY to choose from in both forms.
The internet is your friend...might as well use it..!

Mike