Car is '06 non-S, 111k miles. About 5 times in the past 4 months, if I am in a higher rev zone and push in the clutch to stop the car will die and the Service Light will come on. The car will fire right back up and the service light goes away in about 10 seconds. For example, I was going up a relatively steep street in second at about 3.5k rpm and push in the clutch to come to a stop, car dies.

I can sit in the garage and rev the engine and it comes back down and idles perfectly.

No codes. I have looked for obvious vacuum leaks but see none. Things that I have replace trying to fix and/or maintenance are:

PCV
plugs/wires/coil
front O2 sensor
MAP sensor
air filter
fuel filter
clutch switch on master cylinder

Frustrated because can't figure it out. Any other ideas before I seek professional (ie $$$) help?

 

Quick question....ever down shift? When you push in the clutch, do you leave the gearshift in gear or go to neutral?
I only ask cause it sound like the transmission is not disengaging....aka, a bad/sticky/melted throwout bearing, usually from riding the clutch....the mini uses a plastic bearing, with a metal cap....
Proper stick shift driving usually includes a downshift....Rather than just pushing in the clutch till stopped...
I'm just guessing....
Any codes stored?

 

That's definitely not right, but why are you pushing in the clutch to stop at 3.5k rpms? You can wait until around 1k and save a negligible about of gas.

 

No codes stored. Usually it's been going up a hill and light changes so I start to downshift so push in the clutch to downshift but just end up coasting/braking. I actually shift down with the gearshift but just do not engage the clutch. I have no idea on condition of the clutch since I've only had the car 4 - 5 months but it grabs pretty well.

Not being defensive but I've been driving manuals for 30 years and never had a car do this. I'm wondering if it's fuel pressure related because it's either when I'm heading up a hill or when the fuel tank is below 1/2 tank. But that doesn't make sense to me because thought symptoms of bad pump were at normal driving - not at idle rpm.

 

It's definitely the unexpected stop where I get cut off or someone stops short in front of me.

 

Lots of first time stick drivers are getting into gen1 cars as they drop in $$...so wanted to be sure you knew what you were doing. Lol....
There HAVE been a couple (that I know of) mini's that has had a hard plastic/rubber fuel line IN the TANK...connected to the pump split...one of the guys to have it happened is around...
I'll see if I can remember the Username/thread....he might pop in if you are lucky.

 

Is the pressure regulator part of the pump? The fuel filter was the original so maybe it's shot the pump.

I will say that the clutch on this car is much stiffer than my Miata's. Guess I was too pampered.

 

OBD wires under the carpet getting moved somehow? Or some part of the wiring that is near the clutch pedal under the carpet? No experience of water soaking in that area? My line of thinking is what would halt the car, throw the Service light, but not leave a code? And how would it not leave a code in this scenario? Some monitored critical system loses its connection somehow by pressing the clutch in, intermittently sure, but that short keeps it from delivering the failure code to the management black box.

 

Can't figure out why no code. When I got home today after I had to restart I plugged the reader in and nothing stored. Both EML and Service light light up. I hear a clicking noise when I push in the clutch that sounds like a switch, I assume that it's the new switch on the clutch master cylinder.

Zippy - ?clutch slave. I bled it a few weeks ago and not leaking but it does appear to be the original. Maybe it's not completely disengaging transmission?

 

I bought this clutch switch from ECS but can't figure out where it goes.

http://www.ecstuning.com/Mini-2006-C...utch/ES168162/

 

It's not the clutch otherwise it wouldn't stall the engine up less you were stationary and you'd be well aware of the bite point and meshing being unpleasant.

You sound like you are on the right track with the air and the fuel. When I go uphill at a freeway exit on mine and dip the clutch to coast up to the junction, I loose enough revs to unlock the doors, but not quite stall. It does head to about 500RPM. Happens almost daily on a part of my commute.

I don't know the fix but you are not alone.

See my unanswered thread about it here.
https://www.northamericanmotoring.co...e-driving.html

 

The more I think about it, the more I think it would have nothing to do with the clutch...rpms are too high to make it stall if it was sticky if I am rereading your first post....safe to say the tranny is smooth, and easy in/out.
Also the clutch safety switch would have nothing to do with it (somebody mentioned it)....that ONLY prevents the starter from cranking if the clutch is not in...so the car can't jump jump ahead unexpectedly....
A stall with a sudden rpm/load change.....I would look around for any loose wires...maybe check the coil terminals for corrosion...check the wires maybe.
No code stored is not expected (had a Honda civic with an ignition issue years ago....same type of thing)....
Hmmmm....see you did a coil/wire swap already......
Double check the engine grounds....both battery and engine mount? Not sure where on a non s .

 

I'll have to dig around check for the ground. The one near the passenger engine mount is good (replaced the mounts) but not sure where others are.

The car does appear to have exhaust leak near manifold but can't reason why that would do anything.

 

I was thinking about this on the way in this morning. What sort of Idle Control Valve arrangement do we have? The ICV may be fully closed and if the throttle snaps shut when you jump off the fuel, a sticky and slow ICV may cause a stall.

 

If this is the cause, I think it would eventually throw a code after repeating enough times.

Ground wire to the OBD and connected systems? I think some short is in the path to wherever the codes are stored, or that box is not grounded effectively. Most other "in-motion" causes would do it when hard on the brakes or over bumps - not limiting it to the clutch and high rpms.

What is the part that manages the high rpm cutoff? The rev limiter?

 

Thought about an ICV because I had to replace once on my Miata. Not sure how the Mini is set up.

I am going to have to check the grounds tomorrow when I'm off. I know the car will store codes because I set it off when I cleaned out the throttle body. (It was completely black inside - wonder if the person even used an air filter).

 

If the throttle body was dirty....
You might want to try running a can of seafoam through the pcv....clean up the sensors... Maybe everything else is gunked up too....

 

The engine is a W10 I believe in your car. From what I'm reading it used the motor driven throttle body to set the idle.

https://www.northamericanmotoring.co...e-iac-mod.html

As for codes, do you have a generic reader or one that can read BMW deeper codes? A lean measurement may not be enough to trigger a fault but may be accumulated in a counter.

http://www.ebay.com/sch/i.html?_trks...at=0&_from=R40

 

I have a generic reader but it will read pending codes.

 

Additional and more detailed and non OBD2 specific information is available to the BM proprietary commands.

 

Low fuel pressure cuts out the engine, causes a lot of hesitation & doesn't throw codes. Check it w/ a fuel pressure gauge screwed on the shraeder valve on the injector rail. R53 pumps are rated 5.1bar & should give around 55psi, while The R50 is at 4.6bar & should give a psi read around the mid 40s. If you yield lower, then dig into that. My split in-tank hose just gave me 22psi. Imagine the issues I had.

 

Is this something that I can try at home? What kind of gauge do you have? I found an Actron Fuel pressure gauge with Schrader valve. Are they all the same size?

 

Should fit, I borrowed a generic 1 & checked at home. The schrader valve is visible & accessible on the R50(at LH end of the fuel rail). Not so for the 53 as it's under the IC.

 

Interesting post, thanks! Did you manage to hook it up to INPA and if so was there any faults stored? I'm thinking low fuel pressure should be detectable by the ECU.

 

No check engine lights nor stored codes. I kept postponing digging into the pump, til I confirmed the fuel starvation, as it was a bit messy. A friend w/ an 03S recently had exactly same symptoms. Told him to check the hose......exact same case. Easy fix though. Told him to make sure he got the submersible fuel hose like the Gates 30R10. Non-submersible hoses will break in a matter of days.