hey all, so when the car is cold, and i am nearing a full stop and the car has shifted down to its lowest gear, sometimes when i come to the last few seconds before stopping, the car shudders. Its not brakes, i cant even guess where to start. suggestions?

 

Don't drive your Mini when cold, I always idle my Mini until it's warm, usually for 5 minutes.

 

From what I've read, you shouldn't have to idle the car until it warms up. You may have a problem with your HPFP during cold days. This forum post seems fairly similar to your situation except your cooper didn't completely die.

The manual states (on page 98) that you should "not wait for the engine to warm up while the vehicle remains stationary. Start driving right away, but at moderate engine speeds. This is the fastest way for the cold engine to reach its operating temperature."

Hope this helps you figure out what is wrong.

 

While it says this is "the fastest way for the engine to reach normal operating temperature", it's also the fastest way to cause wear and tear. Oil lubes better and piston rings seal better at normal operating temperature, they say 85% of engine wear is at cold startup. On a warm summer day I let it idle for at least 4 minutes, it won't harm your engine to idle for a few minutes when engine is cold.

 

After 4 or 5 minutes you are still not at normal operating temp. Meanwhile, the person who jumps in and starts driving right away is much closer to that temp in the same amount of time. Sitting and idling is probably causing more damage than if you just get going.

 

Read this here. It's not rocket science.

 

This thread got off topic really quick.

To the OP, what year and mileage. I have a 2013 and have experience a sudden drop in RPM when slowing to a stop (stall once or twice) within a few minutes of cold start up. Haven't noticed it in quite a while though.

 

Solution is to not drive your Mini cold, simple no? OP while driving his Mini cold can expect this sort of behavior when it hasn't had sufficient time to warm up, when an engine is cold it idles above idle speed. How is that off topic? OP never said it happened when the engine was warm, give a few minutes.

 

I'm not the OP but to me this is not a solution but a work-around. The car's built in the 21st century, you should be able to drive it when it cold. No other car that I have ever owned has had any issue when cold.

Thinking back to my issue, which was similar, can be attributed to the JB+ (never happened when it was un-installed).

 

OP, it sounds fuel related. Here's a video on testing your HPFP. You may be able to get fuel pressures from a scan tool.



@systemlord: Hey I'm still new here but I followed your link in the post you made. I won't speak to the tone of your responses but I will share a link to a study on whether idling or driving to optimum temperature is better. In the study they are measuring emissions and not engine wear. I admit it's not a direct connection to your comment on wear but it does provide a sound reason for not idling to temperature.

I don't know who Andrew Mackinnon is, the person whose site you linked to. He may be an authority or just a experienced shade tree, I certainly can't tell from his site. The link i provided is from Argonne National Laboratory which is a U.S. Department of Energy laboratory. So I would grant this study a great deal more weight than a poorly attributed website with no testing methods described or suggested.

http://www.transportation.anl.gov/pdfs/EE/642.PDF

 

After reading the treatise on warming your engine at idle for five minutes be sure to click the link to the treatise on the illumnati ruling the world.

 

Try this. You can pick any of them that reference myths you should ignore.

 

when i start my car, i wait for my RPMs to drop to around 700@idle before taking off....i figure by then the oil is fully distributed throughout the engine and im good to go.......if that takes 2 minutes i wait 2 minutes.....if that takes 10 minutes i wait 10 minutes......that my "warm up" period.

 

I'm just curious, jcauseyfd do you believe it's better to drive while your engines cold? Reason I ask is because you never really said one way or the other, I have doubts that you will actually answer anyways.

 

Same. Anything under 1k works for me.

 

At the risk of returning this thread to on-topic discussion, sounds like the OP has an automatic. Most likely, the shudder comes from the slushbox which has never had its oil or filter changed, and acts weird when cold. To check, manually upshift the car to 2nd gear and see if the shudder subsides.

Idling for hours on end to warm the engine, while parked, will do absolutely nothing to warm the tranny.

The OP can either "live with it", or try to perform auto-tranny oil+filter service. Either DIY, or at a dealer/independent.

a

 

Sorry off topic again .Can I ask those people who idle their cars before driving what your obd mpg is reading? Its gots to be F'd up!

 

Sure at the expense of engine wear, I welcome it. Modern cars aren't excluded from heat friction and physics, rings, pistons and all engine parts expand all at different rates. I'm utterly flabbergasted that there are those that believe running an engine cold is a sane idea, no one can deny the facts that oil performs better at 180 degrees, why anyone would want to put a load on an engine when the oil is not at optimum temperature is beyond me.

Next time you get in your car start it up and drive immediately, get on the freeway and go above 4500 rpms because it's safe to do so according to some.

This is my last post on this matter!

 

I think we all agree that romping on the car when not at normal temperatures is a bad idea.

But the question is, for cold car sensible driving, when is the wear appreciable and when does it become a concern?

Waiting for the car to warm up to normal temperature before driving is not practical. This winter I would sometimes idle the car and it would take more that 20 minutes to reach 180F coolant temperatures (sometimes it would never reach it at idle). I didn't have the ability at the time to monitor oil temperatures.

Driving the car sensibly until it is fully warmed up should be acceptable with a minimal increase in engine wear.

This is my opinion. You can have yours. But before you call me and anyone else a moron (which in essence is what you have been doing), please back up your claims with peer-reviewed articles published in scholarly journals. Because so far all you have done is link to some unknown person blogging his opinions on the internet.

 

im sitting at 32 MPG, i reset my average mpg at every fill-up.......

1) we arent sitting there for days....hell, even in the dead of winter i only idle my car for 10-15min. at most.....durring the summer im only idling for 1-2 minutes.

2) the car doesnt use a hell of a lot of gas while its idling, so its not likely to throw off the MPG reading.

 

MINI, BMW, and Porsche recommend AGAINST warming the car by idling. Start, drive right away immediately, don't flog it (rev over 3K RPMs) until the engine oil warms up (200+F, if your car has the gauge).

RTFM.

MINI - page 90 : http://www.miniusa.com/content/dam/m...1107__2008.pdf
BMW - page 168: http://www.bmwusa.com/Standard/Conte...modelcode=143Q
Porsche: http://www.pistonheads.com/gassing/topic.asp?t=1293135


I will BMW/Porsche word over that of any self-appointed internet guru.

Draw you own conclusions, folks!

a

 

Are these the same manufacturer (Mini USA) that claim lifetime transmission oil and started out with 15,000 miles oil change intervals and at a later date changed them? Me no trust anything they say.

Forgive me if I don't trust them, I idled my MCS for 2 minutes today, I seriously doubt if that will cause any harm. Most of us that live in the city have these things called red lights so we have little choice in the matter. I think some are blowing this way out of proportion, it's not like were idling until operating temperatures here.

 

Please don't confuse BMW and Porsche factory engineers who build the engines with their North American Sales organizations that package pre-paid maintenance plans and then pad the margins by extending service intervals. Different orgs, different agendas.

The engineers in Germany designed and built your engines, and have no ulterior motives other than making sure their creations are maintained to last forever.

a

 

While I can not offer any suggestions, my 2012 Justa automatic does the same thing. Sometimes, under idle throttle, before the engine is up to normal temp, just before a full stop, mine shudders slightly as if the front disks were warped. My guess is the EFI doesn't meter fuel quite right in a cold engine idle condition. I just drive it a bit more aggrressively until warm.

 

I blame the alignment and tires. I get more of a shuddering noise at low speed, replacing the brakes did nothing. I tightened all the subframe bolts, one was loose but only made a marginal difference.