156 replies to this topic

[gdudu]

Martin, thanks again, here are some answers

a.  Test the resistance of the 02 sensor heater.   I'm not yet convinced the 02 sensor circuit is perfect.

Yes, the resistance seem to be OK, is 6,2 ohms (the motor is still not cold, but almost)

 

Take off that vacuum pipe to the carbon cannister again 

I have to understand how does this works. I have multiples pipes from the manifold :

One goes to the carbon canister (this is the one I removed) and nothing after (or cannot see)

One goes to the purge valve, but after the valve goes outside motor, in the wing ???

One other pipe goes to the top of injection (above where it come from)

 

I don't understand the logic for this system, I have to learn

 

And what about coolant - are you getting any coolant loss?     Do you have to keep topping it up, even by a small amount?

No, not now. It's OK, but it was not always

In the past I had some problems with the cooling maniflow (where the T° sensor is). I have repaired it

[Sprocket]

I have to understand how does this works. I have multiples pipes from the manifold :


One goes to the carbon canister (this is the one I removed) and nothing after (or cannot see)
I think you are confused. I do not know which pipe you have disconnected, and what you are calling 'carbon canister'. You discuss this wrong. The carbon Canister is under the right side wing.

One goes to the purge valve, but after the valve goes outside motor, in the wing ???
The hose out to the wing connects to the carbon canister. Look up inside the wing, it's a black round canister retained in a metal bracket with a rubber strap. The fuel tank breather line connects directly to this canister also.

The Purge valve is between the engine and the carbon canister under the right wing. Simply follow the pipes.........

[martinrub]

I think its my fault: Ive been saying disconnect the pipe to the carbon canister. I should have been more specific and said disconnect the vacuum pipe from the engine to the purge valve at the purge valve.

[gdudu]

Hi

I've made wew tests

1st test by inserting a resistance instead sensor for intake air T°. I've choose 1K cause the sensor is 3.6K at 5°C, and 2.2 K at 20°C. Then with 1K, I simulate more hot, to try to decrease STFT and then consumtion and CO. T° is to 70°C when I put R, and drop to 40°C when I remove R. But STFT is always about -8%, no change when i put or remove the R. 

 

2nd test as you tell me, when disconnecting vacuum pipe. Here, the iddle is growing to 2000 RPM when I remove pipe, and drop back to 850 when I put it back. STFT is correcting much faster, but always at about -8%.

 

I've also checked the purge valve, it's working (disassemble , test with 12V batt, and blow)

I've checked fuel line abovre the car and in the motor, seem to be OK, no hurt

 

   

 

 

Attached Files

•  Iddle with and without R1K intake air temp - Temp.png   113.34K   1 downloads
•  Iddle with and without R1K intake air temp - STFT.png   108.12K   0 downloads
•  Iddle disconnect and reconnect purge valve - RPM.png   16.13K   1 downloads
•  Iddle disconnect and reconnect purge valve - STFT.png   130.85K   1 downloads
•  Iddle with and without 1KR intake air T°.txt   62.14K   3 downloads
•  Iddle disconnect and reconnect purge valve.txt   177.45K   3 downloads

[genpop]

Have you already reset complete ecu?

When you have downloaded mems-rosco, it's explained on the interactive-tab.

[Sprocket]

OK so I have now downloaded the software and had a look at your data logs. I feel that you have an issue with the coolant thermostat. Nowhere have I seen coolant temperature reach 90c where I would want it before considering emissions test. Coolant barely reaches 80c. SPi thermostat starts to open at 88c.
 

Verify thermostat temperature fitted.

Edited by Sprocket, 26 February 2018 - 08:56 PM.

[martinrub]

Those logfiles are helpful, thank you.   

 

It seems when you are in closed loop, MEMS is properly controlling the fuel.   Yes, the STFT shows that you have a rich condition, so MEMS is taking fuel away from the the amount ir expects to give for each condition (speed, load, temp...)       But that rich condition indicated by STFT could also be due to fuel contamination in your oil.        One thing keeps standing out: you said that "big black smoke at starting", and the plugs are black.     That is definitely not normal.    So forget closed loop running for the moment, this black smoke is clear evidence you are running very rich in open loop, richer than you should be.    I don't know the Mini, but I'm sure that can't be normal.     You said you changed the throttle body unit (which contains the injector and regualtor) and it didn't help, but if there was a blockage in the fuel-return line to the tank, that would raise the fuel pressure to the injector, so we can't assume the fuel pressure must be ok because you fitted another throttle body     And if someone had fitted an incorrect MEMS unit, the fuel map would be wrong.    So there are still 2 questions; is the fuel pressure too high, and has the MEMS ECU been changed and perhaps an incorrect one fitted?   (The compression test is still a valid test to be done to rule out other factors.)

 

The "big black smoke at starting", is that only when cold or does it happen when hot as well, and can you smell the petrol in the smoke?

 

 

 

Observations:

 

1.   Your Idle Switch (User Defined, 0x80, 0A) doesn't appear to register in MEMS.      Your car is1995 so it does NOT have a switch on the accelerator pedal; I presume, instead, MEMS learns were the idle position is.    On a normal logfile, you will see the Idle Switch at the high position except when the throttle is closed; then it drops to the low postion.    Yours seems to be at the high position all the time.    So MEMS will think your throttle is never in the idling position.   I'm not sure if it is a problem: you haven't said that the car does not idle properly so I assume it does.    On the other hand, if you open the Cold Start and Roadwway 5mn logfile and set the 2 min scale and go to 9.3 min, you are doing 2000rpm, your throttle appears closed (looking at position), the manifold vacuum is high (3 psi), so you are on over-run for about 30 seconds, you are in open loop during this period, all that is normal, but I would expect lambda therefore to drop to 0.2V or less, (because I'd expect the injectore to be shut off at this time) but it doesn't.    I don't know if that is because of fuel in your oil, which might be contributing to a rich condition or because MEMS is not seeing the throtlle is closed..      It probably has no relevance at all to your basic problem but it is an outstanding question.     I don't know what to suggest.   Chapter 14 says "Adaptive idle measurements and fault codes retained in non-volatile memory cannot be lost - even when the vehicle battery is removed.   If the ECM from one vehicle is transferred to another vehicle, the contents of the non-volatile memory will also be transferred, unless a fault code reader is used to erase the codes and tune the engine to the new setup."     I am very reluctant to suggest clearing all settings using Leopold's mems-rosco unless you were sure the MEMS ECU had come from another car or unless you had a spare MEMS that you knew worked on your car.   I have done this reset on my car several times, but the first time took a great leap of faith!    But I don't want to suggest anything you might regret doing.

 

 

 

2.    You have set a fault code on the Air Temp sensor.     Even so, your air temp sensor seems to be responding to changes in temperature, rather than registering a constant default temperature.   So, even though you have the fault code, MEMS seems to be accepting its signal.   Nevertheless, you will want to clear that fault code some time.      Leopold's mems-rosco will clear faults.

 

 

3.     Whilst there are some possible concerns about the length of time it took on one of your logfiles (3 min) for the oxygen sensor to start working, when it does work it seems to be working as it should.    Unfortunately, we would need an osciloscope to check that the high-low or low-high switch rate is 0.1 sec or faster, but using MEMSAnalyser and comparing your lambda graphs to others, certainly at higher engine speeds, the sensor appears to be performing fairly well.       There are further tests that could be done but I don't believe that is where your problem is, and maybe that's something for later when the cause of your rich condition is fixed and the oil is changed.   By the way, do you know how many miles the sensor has done, and if it's a replacement sensor, is it the correct one and not a "universal" one?

 

 

 

 

A few years ago I got on ebay a fuel gauge and adapter with a blankin plug; it was quite cheap, but I can't see those kits now.    I cut the rubber fuel pipe in ithe engine compartment and fitted the adapter.   IfI need to measure the fuel pressure, I unscrew the plug and fit the gauge.     My working fuel pressure is a little over one bar according to the manual, So I got gauge that maybe measures 2 bar or slightly more (I'm not at home, so I can;t check).       I have found something similar on ebay.   The gauge is very much like the one I got but the adapter seems expensive, and as I said, my gauge came with the adapter

 

https://rover.ebay.c...tm/323091972452

 

https://rover.ebay.c...tm/272876347705

 

and these seem very expensive just for possibly one use; all the more so if it confirms you have normal pressure!    I didn't pay anything like those prices

 

https://www.ebay.co....pIAAOSwcN1ad05h

 

 

I'm sorry it's such a long post and that I don't have a cheap solution to verifying your fuel pressure.

Edited by martinrub, 27 February 2018 - 09:16 AM.

[genpop]

Hi,

additionally to all the suggested work, I would check the size of the fuel nozzle. There are some numbers on top of it.Somewhere here in the forum you will find the right size.(Or compare it to the original one.) If the pre-owner of the throttle-body changed the nozzle with a too big one for better performance, the ecu will not be able to regulate this by shorter opening times. It's just an idea!

For the fuel pressure, you may take a very cheap manometer from a bycicle pump , then you need a y-piece from your windshield washing system and  two rubber hoses. Take off the rubber hose coming from the gas tank going on to the metall hose before the throttle body. Put the y-piece in between and have the engine running.Should be between 1 and 1.3 bar.

[gdudu]

Thanks to everyone, very interesting your answers, but very hard for me to understand, even with google traduction, this take time for me, and I am never sure to have a good interpretation, then sorry if I don't. But soon I will be bilingual :)

 

Have you already reset complete ecu?

When you have downloaded mems-rosco, it's explained on the interactive-tab.

Yes I think I have reseted the ECU, with contact on, and making accel/decel at 10 time (I hearded a little noise clic-clic in the motor)

 

 

I feel that you have an issue with the coolant thermostat. 

You're right, I have changed it last year, cause I've changed my water pump and other pipes in the cooling circuit. 

I remember the man gave me a lower thermostat, saying it was better here (sometime in summer the weather is hot, and the motor is heating)

I wonder if this can be the reason of my problems ?But I will change it

 

 

The "big black smoke at starting", is that only when cold or does it happen when hot as well, and can you smell the petrol in the smoke?

This is always, when starting motor. It last about 15 seconds, just the time to go. But I don't know if it smell petrol. I think yes, but not sure.

 

 

  On the other hand, if you open the Cold Start and Roadwway 5mn logfile and set the 2 min scale 

I notice this in log file : when throttle is opended (when I accelerate), the loop is opened, and the STFT is going back to zero (see for example at minute 8). And the STFT never goes above 0%. I don't know if it's normal ?

 

 

 

I am very reluctant to suggest clearing all settings using Leopold's mems-rosco unless you were sure the MEMS ECU had come from another car or unless you had a spare MEMS that you knew worked on your car.   I have done this reset on my car several times, but the first time took a great leap of faith!    But I don't want to suggest anything you might regret doing.

I could do this, but before I have to test others things, and find another ECU, and make Leopold's mems-rosco work. I've downloaded from here https://github.com/L...dG/mems-reader, but I don't succeed to make it work on my PC. 

And I don't understand all differences between mems rosco, mems reader, mems analyser, readmems and Leopold. But I have to read   

 

 

 

2.    You have set a fault code on the Air Temp sensor. 

Normal, it appears after my tests with putting a 1K resistance instead. I would clear it, I will see if I can with mems-gauge 0.2

 

 

 

By the way, do you know how many miles the sensor has done, and if it's a replacement sensor, is it the correct one and not a "universal" one?

My lambda seem to be an original, but not sure. The car is betwwen 100000 and 300000 km, I don't know. Last year I've tried to change it, but finally I coulnd't remove the old one without removing all the exhaust, and I stopped. I was not sure it could be the cause of my consumption, the I stopped. 

 

Before buying a fuel pressure kit (and time to have it), I think to make other logs file, and I will do the same with the other injection bloc I have, to compare and see if there are some notable differences. I think it will be the same but it would be useful ?

 

For the fuel pressure, perhaps I could try to see in the tank if the fuel return ?

Edited by gdudu, 27 February 2018 - 02:39 PM.

[martinrub]

very hard for me to understand, even with google [Translate]. Whatever you dont understand I will try and explain more simply.

See genpops excellent idea, above, about making a manometer - and his idea to check the injector is the correct one, though, did you say you changed the injector? Even if you did, take genpops advice and check it.

Resetting the idle: is that this procedure?

http://forums.mg-rov...why-how-308503/

Have you just done this? If so, does the Throttle Switch now show Low in MEMSAnalyser when the throttle is closed?

By all means look at the thermostat, but remember that the black smoke is there even before the engine has started to warm up.

This is always, when starting motor. It last about 15 seconds, just the time to go. But I don't know if it smell petrol. I think yes, but not sure. This is whilst the oxygen sensor is warming up, before it has started working. You are in open loop at this stage; MEMS is not yet controlling the fuel through feedback from the sensor.

I notice this in log file : when throttle is opended (when I accelerate), the loop is opened, and the STFT is going back to zero (see for example at minute 8). And the STFT never goes above 0%. I don't know if it's normal ? This is normal, exactly as it should be. You accelerate and you want extra fuel for power; you dont want MEMS trying to give you a mixture of 14.7:1 - thats for cruising when you have finished accelerating. The STFT shows zero when this happens; it only means that STFT is off. You dont want MEMS taking fuel away when you put your foot to the floor: you want power! But when you have fixed your car, you will see that, in closed loop, STFT will usually be above zero and below zero by similar amounts and for similar times; it doesnt have to be exact, but your shift of -12% or so, shows something is not right. That number is too big. So that part is not normal.


And I don't understand all differences between mems rosco, mems reader, mems analyser, readmems and Leopold. For now, mems-rosco is Leopolds program and you run that in the car and make your logfile with it. MEMSAnalyser is Al Richeys program: you open Leopolds logfile using it when you have made your logfile, and it displays the graphs. I will come back with more instructions about mems-rosco to make sure you have downloaded it properly.



My lambda seem to be an original, but not sure. The car is betwwen 100000 and 300000 km,. Thats a big range of uncertainty! If it is that old, it would almost certainly help to replace it, but not until your car is fixed, I think. And yes, it will be difficlukt to remove. There is a special socket.     https://www.ebay.co....JIAAOSwFdtXxAIq

 

And PlusGas penetrating oil or similar (https://www.ebay.co....AAOSwySVaAvqq) soaking overnight does help. Even so, you could still need a new downpipe, especially if it is badly rusted or there are any holes in it, no matter how small.       Any leaking exhaust gas near the oxygen sensor will cause problems because the sensor needs clean air on the outside of it so it can make a compariosn with the gases inside the exhaust.   If exhaust gas is on the outside of the sensor, it cannot work properly.


Before buying a fuel pressure kit (and time to have it), I think to make other logs file, and I will do the same with the other injection bloc I have, to compare and see if there are some notable differences. I think it will be the same but it would be useful ?. Quite possibly useful, but remember that your biggest problem seems to be when starting, that is, in open loop. So any logfiles should start say half a minute before the engine turns on, when you turn the engine off, swich the ignition back on and leave the logfile to run for another 30seconds. Even if we learn nothing about your problem, it is an excellent practical learning exercise - a far better way to learn than trying to understand a written description. Ive already learned a lot from your logfiles.

And don't buy a fuel pressure gauge until you have explored genpop's home-made manometer idea.

Edited by martinrub, 27 February 2018 - 03:42 PM.

[martinrub]

"I've downloaded from here https://github.com/L...dG/mems-reader, but I don't succeed to make it work on my PC."

 

 

 

 

Can you try again.    Download from here:

 

https://github.com/L.../mems-rosco.exe

 

and when you open it, it should extract to a folder called mems-rosco.     You then open the file inside called mems-rosco.exe.      Give it a minute or so to be sure.

 

I am having problems with it; it won't open for me.   I'm running Windows 10 64 bit.

 

Does it now work for you?  If not, what is your operating system?

Edited by martinrub, 27 February 2018 - 04:39 PM.

[genpop]

or try "minireader" at the same place, but then you have to build a directory "logs" inside of this directory.

[Sprocket]

Start with the basics. Coolant thermostat needs to be 88c part.

With 72c which I think you have, the ECU will always be in warm up (on choke if it were a carb).

I do think there are other issues with general tune of the stepper motor and idle air, but I do not see anywhere in the logs for stepper position. Im sure its there but its not instantaneously obvious

[genpop]

Hi Sprocket, if you have the memsanalyzer  take the last tab "user-defined" , then  user-defined button Page 0x80, next field Byte, choose 12 intake air control

[Sprocket]

I type for better translation. I hope is OK

 

Note before going further. When changing the thermostat for 88c, make sure it is between the thermostat housing (outlet) and the sandwich plate. It must NOT be between the sandwich plate and the cylinder head.

 

Looking at the intake air value, if the digits should be counted as the number of steps, there are too many, which means that the idle stop is incorrect. Before asking you to change anything, I ask you to install the correct temperature thermostat, and to confirm the warm idle temperature above 88c, ideally 90's.

I see the idle is low in 700, can you confirm? is the software reading RPM lower than real?

If you fail to reach the basic setting for SPi, do not follow the rich mix.

 

Me, I would ask.....

1. Does the engine rise to correct hot temperature, high 80, low 90s? (actual motor temperature, no CTS reading)
2. Does CTS reading match actual motor temperature? (one or two degree difference acceptable)
3. Is the number of air steps close to 35 or 40?
4. Is advance 15 degrees + or - 5?
5. Is idle speed 850rpm?
6. Is lambda voltage changing frequently?
7. Is MAP near 500mmhg/35kpa/5psi?

 

Looking at data from your engine, answers following in order of priority......

1. No...... Solve. Change coolant thermostat for 88c
2. Yes....OK
3. No...... Solve. This is normally done with the diagnostic tuning program, but can be done carefully without. (Repair number one first)
4. Yes.....OK
5. No ..... Solve. (Repair numbers one and three first)
6. Yes......OK
7. Yes.....OK