Rebuilt S63 - Misfire Help!

[DrVirz]

Bit of an update. I haven't had a lot of opportunities to work on the car.

I did however change the vanos solenoids. Unfortunately no good, still have the same issues!

This weekend I will get around to testing resistance in coil cables from DME, re-check plug gaps. Considering throwing new coils at it however as mentioned, have swapped them from cyl to cyl with no luck.

If that fails, I will probably pull the injectors and have them tested.

[DrVirz]

Another update, got around to checking plug gaps. They were about 0.029 (0.74mm). I opened them up to 0.8mm which I believe is stock, still no difference.

I tested the coils with one of those cheap coil testers (link below). I'm sure they are far from accurate however all I really wanted to test was consistency across all coils. There were definitely some discrepancies, with coils sparking between 2.5kV to 3.5 kV. Again, I'm sure this tool is far from accurate however it at least shows some discrepancies.

At this point I'm thinking of throwing new coils at it. On the hunt for a set of 8 eldor coils. I doubt this is the issue however relatively inexpensive and probably needed after 100km anyway.

https://www.repco.com.au/tools-equipment/automotive-tools/engine-drivetrain/toledo-hd-spark-plug-firing-tester-302167/p/A9485434?rgfeed=true&cid=google-shopping&utm_source=google&utm_medium=cpc&region_i d=100009&gad_source=1&gclid=CjwKCAiA1fqrBhA1EiwAMU 5m_0lnHvnbFbjsajqwO-5Tk-DlD5eSnX6wWsYYaNh54rJu687TGfmgUBoCqIoQAvD_BwE

[DrVirz]

Bit of an update (no luck).

I checked the timing on Bank 1, all is good.

Checked for continuity and resistance on all coil and injector leads (from plug to DME). All under 0.6 ohm.

Replaced all coils with Dinan as I couldn't find Eldor coils.

Still the same issues!!!

Next stop might be a shop unfortunately.

[DrVirz]

Looking back at the knock sensor values, it may be possible that they are pulling ignition timing? Not sure why all knock sensors are out this much.

Two vids below of the values on Cyl 1-4 and 5-8 vs ignition timing. Ignition timing jumps around at idle, is this normal?

Any chance someone can make a vid of their values at idle?

https://youtube.com/shorts/QlU6epAFQ-o?feature=share

https://youtube.com/shorts/bvsUyKHfNJQ?feature=share

[DrVirz]

Thought I'd give a bit of an update if anyone is still following.

Replaced all injectors, still no good

Decided to run VANOS solenoid ABL again. I am not getting the error - Adjustment is too slow or the setpoint value cannot be reached. Quite odd as I have run this test before without the error.

I wonder if my new vanos solenoids are faulty, hmm. Seems to be occuring across all solenoids, perhaps an oil pressure issue. Will update as I discover more...

[tfunk88]

Man, I hope you’re able to figure it out! Good luck!

[Chilled]

Did you end up replacing the knock sensor?

[DrVirz]

Originally Posted by Chilled

Did you end up replacing the knock sensor?

Not yet. I am trying to avoid pulling the motor if I don't have to. I am hoping the knock sensors are throwing high voltages due to misfire/motor running rough causing vibration.

At this point I'm thinking perhaps a faulty (new) vanos solenoids or possible cam gears. Cam gears may be work or the journal's partially blocked from previous motor that spun 2 big ends, hmmm.

[nedrobmas]

I would check the two small ground wires near # 1 and 4 injector connects, spark plug gaps, for bent pins on coil plug, dirty in coil connectors, injector for bent pins and dirt in connectors, everything from the tip of the spark plug to the source.

[Chilled]

Based on the voltage, that #4 knock sensor is done for. You will probably need to get to it at one point or another.

It is interesting how wide the knock values are between the banks tho. I'm not home, so cant see what mine is doing.

Btw, did you end up trying DeepODB?

[Melbf85bm3]

Hey i have a similar issue. rebuilt S63TU and misfire problem. idle is jumpy but drives fine and doesn't miss a beat.
It goes into limp mode after idling fo long periods or when its hot (but only when its at idle ie. stopped at traffic lights, but not always.
I have new everything.
would like to know if you've found a solution....

[Chilled]

Well I stand corrected, DeepODB doesn't seem to log both DME simultaneously in any meaning full way. Only focuses on 1, and the polling rate can be 10s.

It also looks like BMW doco on the voltages maybe off.

I had 2 sensors that shows way past 12v and no knock trigger.

[DrVirz]

Hi all,

Sorry for the delayed response.

Yes, I have checked continuity and resistance on all grounds as well as ignition and injector circuits, all checks out find. I have also gapped the plugs. Keep in mind, plugs, injectors and coils are brand new.

Interesting regarding your knock voltages. I had originally thought this was the issue and it was causing the car to run in limp mode or similar, but would surely have a code if that was the case. I got DeepODB but haven't had a chance to use it yet.

I am currently waiting on 4 new Pierburg Vanos solenoids to arrive. Hopefully get them in next weekend.

[Chilled]

I tried to relog with BimmerLink, it seems to roll up the values per cylinder, ie 1and 5. But I did see the same voltages as in Deep.

Did you try just pulling the injector and coil plugs on cyl 4 and see if it runs smoother and or other pistons? Did you end up getting a better compressions tester?

Seen this,
https://f15.bimmerpost.com/forums/sh....php?t=2074941

There was a re-fresh for the coils (sometime in 2015/2016) and not all coil plugs are the same. The connecter will not sit all the way in.

[suitedcboy]

I worked in tech support and training for a car manufacturer, not BMW. Misfire counters climbing but not setting misfire codes, often it will set p0300 (can't recite the BMW hex code for this). This problem is a post engine R&R or trans R&R related in majority of cases. Anyway, it is irregularities with crank position sensor system. The aperture surface of flex plate (flywheel) has little tolerance for runout. It is easy to dent them in handling engine and mating to trans. The misfire detection is using the rhythm of slowing and accelerating of crankshaft for compression followed by combustion as it sees peak to peak periods. There can also be suppression problems when the trans to engine surfaces are dirty/greasy as aluminum is a poor shield for magnetic field anomalies. dirty bell housing disease usually shows as long cranking together with anything else as the starter throws some serious magnetic flux lines across the flex plate. The learning of flywheel irregularities, ones that can be adapted for, is usually accomplished by coast downs. You can manually select 1st and then get to 15kph and then lift throttle and let engine speed drop as speed drops to 1000 RPM or lower and then gently accelerate again to 15 KPH. Repeat 6 times and then see if misfire counters stop increasing and the roughness goes away. I do not believe there is a place to see the aperture surface (the flex plate edge ring with all the rectangular openings and a spot with no aperture) and checking for depth to surface to see if it has dent(s) would be tough but possible.

[Chilled]

dumb question. For the new injectors if you have the EU5, you did code or do the smooth running (i think) test?

Also, whats the latest sets of codes? Just the Vanos setpoint? on one bank or both?

*Edit*. Good point on the crank position sensor. When you were re-installing the fly wheel? Did you have/line it up with the locator pin location? Granted, if you miss aligned this, it probably would not start and you would be getting a crank position sensor error.

[suitedcboy]

I am talking about the aperture surface around perimeter getting dented. The pin on crank makes improper placement unlikely but mishaps with flexplate while engine is out and when installing is easy to do. The two DMEs on the v8s can lead to some anomalies than single control engines can't have. The two cylinders counting misfires are in the same DME control.

[Chilled]

That locator pin is removable tho. So if you don't put it back in, they flywheel goes back on any which way. But again, if that was miss aligned, it wouldn't start.

[DrVirz]

Hi all,

New pierburg solenoids in, no change.

Very interesting regarding the crank angle sensor and flex plate. I have had this in the back of my mind for a while, as it was a struggle to get the engine lined up correctly with the box and have wondered if I perhaps damaged/warped the flex plate in some way, shape or form.

Unfortunate that it would require pulling the motor again to check agh..

[Chilled]

I doubt that's the issue, as when I saw a mate have it miss aligned. The engine simply would not start. But to check, you would need to drop the gearbox.

• Did you end up getting a cheap oscilloscope? Because you maybe able to see if TDC from the crank and bank 1 (piston 1) line up. or is there a way to view this in ISTA/other tools?
  
• Did you end up getting a proper compression tester?
  
• What about pulling the plugs(injectors, coils) on the knocking cylinders. To see how it runs with them off.
  
• Given everything replaced, whats the current list of issues/errors.

Maybe***
If reading correct, The error is only on 1 bank. If TDC from crank and cylinder 1 line up, maybe swap over the cam gears between banks?

[DrVirz]

Originally Posted by Chilled

I doubt that's the issue, as when I saw a mate have it miss aligned. The engine simply would not start. But to check, you would need to drop the gearbox.

• Did you end up getting a cheap oscilloscope? Because you maybe able to see if TDC from the crank and bank 1 (piston 1) line up. or is there a way to view this in ISTA/other tools?
  
• Did you end up getting a proper compression tester?
  
• What about pulling the plugs(injectors, coils) on the knocking cylinders. To see how it runs with them off.
  
• Given everything replaced, whats the current list of issues/errors.

Maybe***
If reading correct, The error is only on 1 bank. If TDC from crank and cylinder 1 line up, maybe swap over the cam gears between banks?

I haven't got an oscilloscope yet, it's on the list if all else fails.

I did get a compression tester that screws into plug thread, reading about 165 across all 8, so a bit low but definitely enough compression for the motor to run.

I tried pulling the plugs on coils and injectors on cyl 2 and 4. This made little (if any) difference, hard to tell but I'd say no different. Therefore I think it's a safe assumption that cyl 2 and 4 aren't combusting. They definitely have spark as I tested this a while back. If the flex plate is damaged like previously discussed, will the crank angle sensor tell DME to cut fuel to affected cyls?

In a nutshell, there are no ISTA errors/codes now. The car idles rough (seems to be missing), particularly at approx 900rpm. Higher in the rev range it isn't as bad.

[DrVirz]

I have had a bit more time today to spend on it.

I ran the car and unplugged then plugged back in each individual coil (all 8). On the contrary to what I said yesterday, there is a slight difference when unplugging coil 2 and 4 (and every other coil), only slight however. Therefore, I do think every cyl is combusting.

Therefore, I am thinking that the issues aren't isolated to cyl 2 and cyl 4, which were originally the cylinders counting misfires on ista (no codes).