Hi there, i have only just joined to today, but have to admit i have used the information on this site a number of times to try and get a Mini i've purchased for my son running.
So it's a 2010 R56 Mini Cooper, manual N16 1.6 petrol engine. I bought it 'supposedly' running from an auction, got it transported home and guess what, it wasn't runing at all. I've tried to negotiate with the auction house but no refund, so my son and i are working thourgh the many issues the car had, we seem to have resolved them all, aside from the fact we can't keep it running.
There are no error codes whatsoever (aside from 5DE3 DSC control unit, encoding error), we've put in a new battery, new sprark plugs and coils, cleaned and thested the injector and rails which all work fine. We've had the rocker cover off as there was a little oil in the spark plug wells, so new seals there. I've tested the low pressure fuel pump which is working fine and i've done a compression test on all 4 cylinders and they are each showing between 200 and 205 PSI, which does seem high compared to other reading i've seen on here, but could it be becasue of the new gasket and seals? So it's got; fuel, spark and air. Although i can't seem to find a MAF anywher eon this particlar car?
When we got the car the there were dozens of codes and the DME was not communicating, i tried to get it cloned but was advised it was completely unreadable and dead, so i've had to buy a DME kit, with CAS and Key etc on eBay. That allowed me to clear all the code asdie from the mentioned above 5DE3 which i think means i need to pair the FRM with my new CAS, which i'll do when i get the car running.
So after the DME kit change, the car at least started, but it dies seconds later, i can prolonge it if i depress the accelarator, in fact i could keep it going for several minutes, but as soon as i stop massaging the accelartor it stalls.
I've had a mobile mechanic round who did a lot of head scratching and told me how complicated the mini engine was, then walked away.
This will be my sons first car and we are really keen to get it going, as aside form the not starting probelm it's was a nice car with some good service history. Looking at the mileage i think the car had been standing for at least 12 months, so i thought maybe the petrol had gone bad, so i pumped out as much as a i could and put in 5 litres of new petrol but car still stalls, i attach a video below so you can hear the car start, stall and how it behaves when i try and keep it running. I'm sure someone will know the desperate noises the engine makes well. Thanks for your time

 

Problems attaching video, but it's now there

 

What is your fuel pressure?

 

Hi thanks for taking the time to think about my problem, it’s ok at 3.5 bar

 

That you can keep the engine from stalling suggests a fuel supply problem.

But one can't rule out a throttle problem.

And given the condition of the car I'd at least remove the engine air box and engine filter and as much other intake piping necessary to ensure there is nothing in the intake that could be interfering with air flow into the engine.

 

Don't know how much help I can give but I had a similar problem with a Turbo Acura RDX. turned out to be a collapsed catalytic converter.

 

It is a possibility. One can check crankcase vacuum which should be less than normal. (1inHg to 2inHg). A more involved test is disconnecting the converter and doing away with the suspected blockage.

 

Hey thanks for the comments, I've removed all the air filter and box, back to the throttle body. I've filed the throttle body when starting the car, video attached, not sure if that's behaving normally or not?

I did take the throttle body out, it was pretty mucky on the engine side, secondhand ones on eBay are around £20, so if you think mine might be misbehaving, it's not an expensive option for me to try another? I'd welcome your thought on the video.

 

Never even considered a catalytic converter issue, I'll see if it's an easy unbolt and remove to see if that makes any difference. Thank you for the thought.

 

Clean the throttle body and reinstall it. That might fix your problem.

 

Had a throttle body fouled with oil from a failed air/oil separator (AOS) with another car of mine. When I exposed the throttle body a drop of black oil was hanging from the butterfly valve. A cleaning is all the throttle body needed. That and I had the AOS replaced.

Not sure you'd need to replace the throttle body just because its mucky (aka dirty). But a cleaning is certainly called for.

 

The back of the throttle body was covered in dirty oil, so I did clean and reinstall but no fix. Is the air / oil separator under the black cover on top of the rocker cover, if so I’ll pop that off and see if that needs a clean and replacement. Not sure if there should be oil around the back of the throttle body and the seal where is connects to the engine block but there is, could that be related to my problem? I’ve also taken the spark plugs back out, and given I’ve only tried to start the engine a dozen times since I’ve installed them I was was surprised to see a black soot build up on all of them, is that normal so quickly?

 

Do you have access to a scan tool? If you do, connect it via OBDII, and use OBDII; do not select MINI. Pull up your long-term fuel trim under live data. What's the number?

 

Not sure where the "AOS" for the MINI is located. With the engine that had a bad AOS it was a separate component that bolted to the engine. But absent something similar with the MINI then it has to be part of the valve cover. (Other car engines this is where the "AOS" was located.)

In the case of what proved to be a bad AOS it was flowing way too much crankcase air which was vacuuming the oil vapor out at such a rate too much oil vapor made it to the intake. The amount of air/oil vapor actually managed to foul -- quite a bit -- the throttle body/butterfly valve which was located just up stream of where the hose from the AOS connected to the intake manifold.

Soot on fresh plugs may be a sign of trouble. But maybe not. I note you have started the engine a dozen times but I bet have not let it run any length of time. A cold engine will run rich. It is possible the plugs to collect a bit of soot but with more engine run time this would burn away.

As mkov608 offered, view long term fuel trim. And observe short term fuel trim too.

 

Thank you for the advice I do have a scan tool so will check the long and short term trim numbers tonight when I’m back from work and report back. Thanks again

 

Well lots of progress this evening, I welcome your thoughts and I don't want to tempt fate but I really feel like you are drilling down into this problem for me.

So I have a Foxwell NT510 elite scan tool and I ran though all the live data options I could find this evening and I can't find long or short term fuel trim options or data, but I did run all the live data and by balancing the throttle and keeping the car running for 5 minutes I can report as follows;

Operational Smoothness Values
Cylinder 1 lowest -2.74 highest 2.66
Cylinder 2 lowest -1.19highest 1.83
Cylinder 3 lowest -3.35 highest 14.74
Cylinder 4 lowest - 0.14 highest 3.59

Motor operating values
Battery voltage 14.51v
Engine speed 1033.50 1/min
Coolant temp 72.75 Degrees Celsius
Intake manifold pressure after throttle valve 953.12hpa
Current throttle valve opening angle 13.11 drosselklappe
Intake air temp 33.75 Degrees Celsius
Air-mass flow, hot-film air-mass senso 1062.00 kg/h
Tank vent valve duty cycle 28.13 %
Adjustment factor model intake valve 0.84

Oxygen sensor emissions control
Oxygen sensor voltage upstream of catalytic converter 1.11v
Oxegen sensor voltage downstream of catalytic converter 0.93v
Oxygen sensor emissions control - no reading just says 'not defined'
Additive fuel mixture adaptation factor 0.00
Additive fuel mixture adaptation 0.00
Oxygen sensor actual value 1.00

Valvetronic
Eccentric shaft nominal value 48 to 53
Eccentric shaft actual value 49 to 57

Misfire detection
Misfire rate cylinder 1 - 4
Misfire rate cylinder 2 - 1
Misfire rate cylinder 3 - 2
Misfire rate cylinder 4 - 4

Hopefully some of the above figures leap out to those in the know???

So this is where it gets interesting, whilst balancing the throttle to get the data, the car suddenly started to idle on it's own it was still a little lumpy it ran for a few minutes then died, at this point I saw steam coming from my engine area. Having checked somehow the water pipe that runs from my expansion tank to the engine block area had blown off the engine block area, so water was everywhere.

I'll get some coolant and refill, but also hope that bizarre occurrence may mean something to someone given the problems I'm having, all in all an eventful evening.

I genuinely look forward to any words of wisdom, I do feel like we are making progress here, so thank you.

 

Some of these:

Oxygen sensor emissions control
Oxygen sensor voltage upstream of catalytic converter 1.11v
Oxegen sensor voltage downstream of catalytic converter 0.93v
Oxygen sensor emissions control - no reading just says 'not defined'
Additive fuel mixture adaptation factor 0.00
Additive fuel mixture adaptation 0.00
Oxygen sensor actual value 1.00

appear a bit odd.

But I don't know if the #1 O2 sensor is narrow band or wide band. A narrow band sensor has 4 wires. A wide band has 6 wires.

That there is a 1.11V reading suggests wide band. But with wide band sensor there shouldn't be a voltage reading but a lamba reading. The ECU receives the signal from the sensor and processes it to come up with the lamba reading, which wants to hover right at 1.0.

Now some scan tools attempt to try to convert the lamba number back into a voltage level. This doesn't work well...

Correction. The ECU returns 4 byte values:

Oxygen Sensor 1
Bytes: AB: Air-Fuel Equivalence Ratio (lambda,λ)
Bytes: CD: Voltage

I've only had a chance to view wide band sensor info briefly. And my scan tool provided a graphic a moving line plot of the lamba. I don't recall any readings.

Tomorrow I'll connect my scan tool to my 2023 JCW and see what is available.

The downstream sensor should be narrow band and these read from a min of 0V to a max of 1V. A reading of 0.93V is very high. Wants to be down in the 0.6V to 0.7V range. The high reading suggests excess air. But with the uncertainty about the #1 sensor, and that there is no reading for the oxygen sensor emissions control, that it is not defined, may mean the sensors are not yet working properly and the 0.93V reading can't be relied upon to make any diagnosis.

Thus based on my experience the sensor readings are of no value.

However I think you are dealing with the same behavior as before. And based on what you wrote before I offered a fuel supply problem has to be considered or possibly something in the intake that might be blocking air flow.

Also the throttle body was dirty. And you reported you cleaned it. Is it showing any signs of getting back mucky again?

 

Couldn't wait until tomorrow to see what my MINIs O2 sensor readings were. So out I went to the car.

Oh, I knew from my previous use of the scan tool that its support of MINIs stops at 2006. Mine is a 2023.

All I could see was Bank 1 sensor 1 amps (milliamps)! And Bank 1 sensor 2 volts. The amps (milliamps) values didn't make any sense to me. But as I remembered with other vehicles the #2 sensor voltage reading hovered around 0.75V.

Was planning on buying a newer scan tool that will work with my new MINI and BMW. Now I have even a stronger desire to get one.

However, I was thinking of a Foxwell NT710 which is an upgrade of the NT510/NT530. Also on my list is an NT650. But with the data your NT530 provided I'm having concerns that maybe a Foxwell is not the right scan tool. However, I find that hard to accept.

Will see what I can find locally or I'll have to order something.

 

The upstream sensor is a wide band sensor; you don't want the voltage on a wide-band sensor; you want the current reading. On a wide-band, negative current indicates the engine is running rich and the DME will pull fuel away (negative fuel trim). A positive current value indicates the engine is running lean, and the DME will add fuel. The downstream sensor is a typical narrow-band sensor. That sensor should range from .2 - .8 volts. If it's not moving from .92, it's fixed rich. One way to tell if the downstream sensor is switching it to take the car for a drive (but that doesn't should possible in your situation), and watch the voltage during deceleration; the number should drop to around .2 volts. If it doesn't, the sensor is faulty. In like manner, if the sensor is indicating .2 volts, and you hold the accelerator to the floor, the voltage should rise to about .8 volts and stay there during WOT (wide-open throttle).

From the data you've posted, you have misfires in all cylinders. Check compression; check timing; and perform a leak-down test if your compression is off on any one cylinder. Book spec on compression is 8-12 bar; with no more than 3 bar difference between cylinders. Leakdown should be <10% in each cylinder.

I've seen faulty O2 sensors (and MAF sensors) cause misfires.

 

Rock, I've got some 2022 Foxwell scan tools left over from SEMA 2022; IM me if your interested. For example:
https://www.foxwelltech.us/product-detail-738.html
https://www.foxwelltech.us/product-detail-726.html
https://www.foxwelltech.us/product-detail-729.html

 

My JCW #1 sensor current reading was cycling from about -0.3 to about +0.4. Wasn't sure the tool was giving me good data for the #1 wide band sensor.

 

-0.3 mA to about + 0.4 mA? It's doing what is should be doing ... switching.

I captured this today while out for a drive.

 

Thank you for the advice I’ve done a compression test and all four cylinder are 200 to 220, which based on other readings I’ve seen seems high?
Ive also now noticed oil in the expansion tank, no obvious water in the engine oil though, could it be I’ve cranked the engine too many times, head gasket issue, or maybe a coolant problem that is somehow causing my start up problems. I’m going give it a good flush and if it comes back.

 

Well, your readings are consistent, if not high. The book spec is 116-175 PSI. I can't remember the allowable difference between cylinders.

It's possible you've cranked it to many times; try again with 5 strokes; you can see the piston strokes on the gauge ... the needle will move up.

 

Hi ran it again with 5 cranks still coming back at around 200PSI?