[bmwlover]

Hello. Have problem with n63 engine. 35000 miles. Injeqtors are good, was not able to find any leaks. What can be the problem? I need to check high pressure fuel pump in bank 2. Can it be done with ista or how to perform this job? Error codes were: 29e1 mixture control on bank 2, combustion misfires cylinder 6 and cylinder 8.

[donkorgyane]

Please check for injector leaks or excessive air leak.

[dil6222]

And then next i would check timing is correct and  test compression on all cylinders

[B1257]

Looked at your pictures, roughness was higher on cyl 1 and 5 with the backround information about the charged N62 engine (H1) from ALPINA I still would say it again it could be a problem with carbon deposits.

We had this problem not only one time, most of the reason was a higher oil consumtion of the rc (the engine is charged with an ASA rc) and therefore combustion process was insufficient. You wrote in your first post that your engine is equipped with index 11 injectors. Injectors before were replaced because of insufficient spray pattern and most of the time more in the dynamic flow range. I found a service sheet from 2014 were I had a problem with a B5 N63 egnine. At the end of the sheet I found a small information that if you have injectors with index 10 or below and you will run in problems replace them all. If your engine has index 11 you replace only the infected injector. Now to find this injector can be a problem, because as I told there are two different modes a static and a dynamic flow range. A working injector at idle speed can work totally different in a mid range engine speed.

Most of the time and this is for all engines the same "high load at low engine speed" called low end torque operation is the range were the engine is most sensitive. Therefore spray strategy is changed to three time injection. The working operation is between idle speed and 2200 rpm and starting from 250Nm tourqe rising.
So if an injector will fail (in a dynamic flow) we have a three time higher probability that a misfire detection can occur at this part of operation.   

Carbon deposits can take bad effects of the injector nose too and change the spray pattern, later the injector is not closing very well. Second scenario is a changed spray angle, for example the hub of the nose is too high the spray angle is to wide and can take effect on the spark. 

Misifre detection works in the way that the second coil (high voltage part, the time when the magnetic field collapses) is monitored via a shunt (remember in the mid 80´s on the BOSCH tester the scope on the high voltage line. You got a scope picture of the ignition) ECU is monitoring the same way and the signal is digitalized and combined with a variance analysis, nothing more. The ECU knows the ignition timing and only needs to take a snap, a short time before and short time later of the signal.
   
Anyway I talked to one of my BMW friends and was asking about problems on this engine. No problems wih the rail pumps at all. Injectors sometimes but hard to find, but most of the time the problem I tried to explain.

He told me try to use a tuneup injector cleaner, one or two times. The cleaner will help the injectors to be working better and remove possible contamination. It can not remove the carbon deposits in the intake manifold, also not on the valve sit ring.

The valve sit ring combined with valvetronic is the second problem. If you have a bad sit ring on the exhaust valve temperature hot spots will occur and can destroy the valve itself or will result in a bad compression. 

Did you check the sparks meanwhile?

Regarding to the question about rail pressure check the module list af the beginning and make a doube klick on the ECU, than a second windows will open, here you can find a list were you can activate different life data points, later you have to push a start or activation button. But Keep in mind a leaking injector can cause different reasons. 

I remember the last post 9 from user node were he explained how the ECU loop is working.

If you dealing with faults somtimes the reason can come from a total different location. 

Very clear is that this fault can not be fixed with a keyboard only operation, but to use the keyboard and read about technical information and the ISTA FUB sheets can help to localize the faults cause.

[karmamule]

Start Abl with missfire detection in ista. Then you must look for the pressur in rail 1 and 2.
when the pressur drops you need to replace the high pressur pump.

[bmwlover]

Start Abl with missfire detection in ista. Then you must look for the pressur in rail 1 and 2.
when the pressur drops you need to replace the high pressur pump.

Drops in bank 2.

---

Looked at your pictures, roughness was higher on cyl 1 and 5 with the backround information about the charged N62 engine (H1) from ALPINA I still would say it again it could be a problem with carbon deposits.

We had this problem not only one time, most of the reason was a higher oil consumtion of the rc (the engine is charged with an ASA rc) and therefore combustion process was insufficient. You wrote in your first post that your engine is equipped with index 11 injectors. Injectors before were replaced because of insufficient spray pattern and most of the time more in the dynamic flow range. I found a service sheet from 2014 were I had a problem with a B5 N63 egnine. At the end of the sheet I found a small information that if you have injectors with index 10 or below and you will run in problems replace them all. If your engine has index 11 you replace only the infected injector. Now to find this injector can be a problem, because as I told there are two different modes a static and a dynamic flow range. A working injector at idle speed can work totally different in a mid range engine speed.

Most of the time and this is for all engines the same "high load at low engine speed" called low end torque operation is the range were the engine is most sensitive. Therefore spray strategy is changed to three time injection. The working operation is between idle speed and 2200 rpm and starting from 250Nm tourqe rising.
So if an injector will fail (in a dynamic flow) we have a three time higher probability that a misfire detection can occur at this part of operation.   

Carbon deposits can take bad effects of the injector nose too and change the spray pattern, later the injector is not closing very well. Second scenario is a changed spray angle, for example the hub of the nose is too high the spray angle is to wide and can take effect on the spark. 

Misifre detection works in the way that the second coil (high voltage part, the time when the magnetic field collapses) is monitored via a shunt (remember in the mid 80´s on the BOSCH tester the scope on the high voltage line. You got a scope picture of the ignition) ECU is monitoring the same way and the signal is digitalized and combined with a variance analysis, nothing more. The ECU knows the ignition timing and only needs to take a snap, a short time before and short time later of the signal.
   
Anyway I talked to one of my BMW friends and was asking about problems on this engine. No problems wih the rail pumps at all. Injectors sometimes but hard to find, but most of the time the problem I tried to explain.

He told me try to use a tuneup injector cleaner, one or two times. The cleaner will help the injectors to be working better and remove possible contamination. It can not remove the carbon deposits in the intake manifold, also not on the valve sit ring.

The valve sit ring combined with valvetronic is the second problem. If you have a bad sit ring on the exhaust valve temperature hot spots will occur and can destroy the valve itself or will result in a bad compression. 

Did you check the sparks meanwhile?

Regarding to the question about rail pressure check the module list af the beginning and make a doube klick on the ECU, than a second windows will open, here you can find a list were you can activate different life data points, later you have to push a start or activation button. But Keep in mind a leaking injector can cause different reasons. 

I remember the last post 9 from user node were he explained how the ECU loop is working.

If you dealing with faults somtimes the reason can come from a total different location. 

Very clear is that this fault can not be fixed with a keyboard only operation, but to use the keyboard and read about technical information and the ISTA FUB sheets can help to localize the faults cause.

Removed injectors and they seam ok. Rail pressures are ok too when I chose module and see live data but when I test misfires from abl, it writes that pressure drops in bank 2. in bank 1 is 978 and in bank 2 is 970. Can it be air leak or it shows only fuel leak?

---

And then next i would check timing is correct and  test compression on all cylinders

timing and compressions are ok.

[duss46]

If it's an E7x X5/X6 you might as well check the DME whether it drowns in water or not, just a tip if you have not done it already.

[bmwlover]

crankcase vent line on bank 2 is leaking. Will keep you updated. Needs 20 days to receive this part.
High temperature is bad for this car. What do you think, will it be good to buy low temperature thermostat?

[B1257]

BMW_N63_en_spark.pdf
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crankcase vent line on bank 2 is leaking. Will keep you updated. Needs 20 days to receive this part.
High temperature is bad for this car. What do you think, will it be good to buy low temperature thermostat?

Due to the compact arrangement (turbochargers in the v-space) the heat output of this engine is very high.
I think it depends on the country you live. In my opinion the revision engine development N63TU was much more better than the first version.

The crankcase vent. should affect all cylinders, not only two of them, may be this is not the main reason for the trouble.

Regarding to the dropping high pressure and misfire problem the actual index of the injectors is 12, service sheet was not updated. Index 11 injectors still can leak under rare circumstances.

After the crankcase vent. repair I would check some more things out.

Important about the misfire, check the sparks and take a look about the attached service information. The sparks would look different if an injector failed (spray pattern angle). Later I would swap the coilpack from cyl 6 to 1 and from cyl 8 to 2. Warm up the engine delete the faults and start a driving sequence with the "high end torque profil" I was writing some posts ago. After driving check the error memory again for misfire, if the faults are moving to the cyl 1 or 2 coilpacks could be damaged, if not the coilpacks are ok.

If the higher misfire rate still exists on the 6+8 cyl. I would replace the injectors on cyl 6+8. If you replace the injectors keep in mind the adjustment:

Special info about injector:
When the injectors are manufactured, a multitude of measurement data is recorded at
specific points in the factory. In this way, the tolerance ranges for injector-quantity
adjustment are determined and specified in a six-digit number combination. Information on
the lift performance of the injector is also added for injector voltage adjustment. Injector
adjustment is required because of the individual voltage demand of each piezoactuator.

An allocation is made to a voltagedemand category, which is included in the number combination on the injector. These data are transmitted to the control unit. During engine operation, these values are used to compensate for deviations in the metering and switching performance.

When replacing an injector it is absolutely essentialy to carry out an injector adjustment.
Rest of the information you will find in the FUB sheet with the "test search" renewing injectors.
Keyword here teflon ring--)) 


Now some more informations you should know.

High presision injection (HPI):
a.) Working on this fuel system is only permitted after the engine has cooled down.
The coolant temperature must not exceed 40 °C. This must be observed without fail,
otherwise there is a danger of fuel sprayback on account of the residual pressure in the high
pressure system.

b.) When working on the high pressure fuel system, take particular care to ensure
conditions of absolute cleanliness and follow the work sequences described in the repair
instructions. Even the tiniest contaminants and damage to the screw connections on the
high pressure lines can cause leaks.

c.) When working on the fuel system of the N63 engine, it is important to ensure that the
ignition coils are not fouled by fuel. The resistance of the silicone material is
significantly reduced by heavy fuel contact. This can cause sparkover at the spark-plug
head and with it misfires.

d.) Before making modifications to the fuel system, remove the ignition coils without
fail and protect the spark-plug slot against the ingress of fuel with a cloth.


e.) Before refitting the piezo-injector, remove the ignition coils and ensure conditions of
absolute cleanliness.

f.) Ignition coils heavily fouled by fuel must be replaced.


Fuel injectors:
a.) Replace the Teflon sealing ring when fitting and removing the piezo-injector. This also applies when an injector that has just been fitted has to be removed again after an engine start.

b.) A piezo-injector provided with a new Teflon sealing ring should be fitted as quickly as possible because the Teflon sealing ring could swell up. The information provided in the repair instructions must be observed without fail.

c.) When fitting, make sure that the piezoinjector is correctly seated.

d.) The holding-down element for securing the piezo-injectors must rest on both injector
wings as otherwise the necessary force is not applied to the piezo-injector.

e.) Do not clean the nozzle-needle tip of the piezo-injector.

f.) When replacing an injector, it is absolutely essentially to carry out an injector adjustment.

g.) When dealing with spark plugs for the N63 engine, it must be borne in mind that there are damage profiles which indicate a fault in the piezo-injectors. Merely replacing the spark plugs alone in such a case will not lead to the problem being rectified.

I know a lot of text, but modern engines have a higher complexity level, therefore reading information before the dirty finger action is always a good idea.