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      12-15-2012, 04:07 PM   #89
GuidoK
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Well to go further in p0171 and a VF570 install:
http://www.m3forum.net/m3forum/showt...p?p=1065722726
This guy has that code (which he didn't notice because his aftermarket istalled gauges blocked the light ), but I dont know the details of his setup (He says its mafless).
Could be unrelated to the pump of course. Not much info in that thread. Maybe the problem is discussed elswhere in more detail.

Quote:
Originally Posted by pokeybritches View Post
Really don't know what you're trying to say here, other than [s]you're[/s]we're way off topic of the original thread.
Off topic or not....I'm not having this discussion by myself....

Last edited by GuidoK; 12-15-2012 at 04:36 PM..
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      12-15-2012, 06:01 PM   #90
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Quote:
Originally Posted by Beedub View Post
its not an arguement, its a really important discussion..... and very good for us ALL to know!!!

Bear in mind the first fuel pump failure happened on a vt2 500 car!!!!! That nearly ended in engine blow!!!!! i think ESS, VF, and G-power should be supplying fuel pump upgrdes imo!

And NO the ECU did NOT pick up this failing pump, Fr8tdog picked it up on a unusual 12 AFR reading!!! no codes, not nothing. ill search back and link it!!
Read what I said. we're interested in the discussion minus the bickering.
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      12-15-2012, 08:10 PM   #91
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Quote:
Originally Posted by aerobod View Post
The injector timing seems to be the issue, perhaps related to fuel map parameters, assuming the engine is operating open loop. The injector timing peaks at 13ms at 6800RPM, it should continue on to about 14ms at 8000RPM, but instead drops to about 11.5ms open time.
Agreed. If it was the fuel pump, the duty cycle would be over 100%, right?
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      12-15-2012, 08:25 PM   #92
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Quote:
Originally Posted by GuidoK View Post
Off topic or not....I'm not having this discussion by myself....
You were out of parameters, and I was trying to reel you back in. In the meantime, the off-topic condition still existed, potentially damaging the thread. tikamak threw the check light because the condition exceeded the threshold.

Actually, I do appreciate the discussion, and you're obviously fairly knowledgeable. When two knowledgeable people come to different conclusions, the best thing to do is to start to pick their brains and find out why, because both can learn something.
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      12-15-2012, 09:16 PM   #93
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Quote:
Originally Posted by pokeybritches

Agreed. If it was the fuel pump, the duty cycle would be over 100%, right?
I believe that would just tell us that the injectors are maxed out; thus needing bigger ones to stay between 80 and 90 percent duty cycle. The problem looks more like something is telling the ECU it needs less fuel, so it's cutting the injection times. As stated, they should continue to increase instead of decrease.
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      12-16-2012, 03:49 AM   #94
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Quote:
Originally Posted by Rated M Roadster View Post
I believe that would just tell us that the injectors are maxed out; thus needing bigger ones to stay between 80 and 90 percent duty cycle. The problem looks more like something is telling the ECU it needs less fuel, so it's cutting the injection times. As stated, they should continue to increase instead of decrease.
YES...... this would be indicating injector max out which isnt going to happen on those new items you have..... im guessing their is no REAL way to see how far were pushing our pumps..... Rated, in fairness, your pump may be more than capable of supplying the fuel BUT due to age and miles its just tired....

how many miles you on now?
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      12-16-2012, 07:36 AM   #95
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Quote:
Originally Posted by Rated M Roadster View Post
I believe that would just tell us that the injectors are maxed out; thus needing bigger ones to stay between 80 and 90 percent duty cycle. The problem looks more like something is telling the ECU it needs less fuel, so it's cutting the injection times. As stated, they should continue to increase instead of decrease.
The reason I think the duty cycle would go beyond 100% with an inadequate fuel pump is because the ECU would continue to try to adapt and add more fuel (just like with injectors that are too small)...

1. ECU adds what it thinks is the correct amount of fuel, based on the map.
2. O2 sensor reports a lean condition.
3. ECU increases duty cycle to add more fuel.
4. O2 sensor continues to report a lean condition.
5. ECU continues to increase duty cycle to add still more fuel... eventually going over 100%.

I think you're right about something telling the ECU it needs less fuel, rather than the car not being able to supply enough. Hopefully VF will clear it up. They recommended I get a Bavarian Technic tool when I had some minor issues with my car (ended up being install error), so maybe it will be my next purchase.
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      12-16-2012, 11:55 AM   #96
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Quote:
Originally Posted by pokeybritches View Post
The reason I think the duty cycle would go beyond 100% with an inadequate fuel pump is because the ECU would continue to try to adapt and add more fuel (just like with injectors that are too small)...

1. ECU adds what it thinks is the correct amount of fuel, based on the map.
2. O2 sensor reports a lean condition.
3. ECU increases duty cycle to add more fuel.
4. O2 sensor continues to report a lean condition.
5. ECU continues to increase duty cycle to add still more fuel... eventually going over 100%.

I think you're right about something telling the ECU it needs less fuel, rather than the car not being able to supply enough. Hopefully VF will clear it up. They recommended I get a Bavarian Technic tool when I had some minor issues with my car (ended up being install error), so maybe it will be my next purchase.
I believe that under WOT conditions the car should be running open loop and there should be no feedback from the O2 sensor (unless a non-OEM wideband sensor is being used).

If the data logging in this case is giving true information, the fact that fuel pressure doesn't move from 6 bar would indicate that fuel flow demand is being met. I would expect that if fuel demand couldn't be met, as the injector open time increases, the pressure could not be maintained due to flow limitations. A slight possibility of maintaining constant pressure but still not meet fuelling demands could be due to pipe constrictions between the pressure measurement point and the fuel injectors, but this would be remote due to fuel pressure normally being measured in the fuel rail itself.

Rated, do you have any more data logging information available (such as fuel trim, throttle position, etc)? Also, I may have missed it, but does your installation make use of wideband O2 sensors, or is it using the standard OEM ones?

Last edited by aerobod; 12-16-2012 at 12:03 PM..
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      12-16-2012, 11:57 AM   #97
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Quote:
Originally Posted by Beedub View Post
YES...... this would be indicating injector max out which isnt going to happen on those new items you have..... im guessing their is no REAL way to see how far were pushing our pumps..... Rated, in fairness, your pump may be more than capable of supplying the fuel BUT due to age and miles its just tired....

how many miles you on now?
The car has close to 27k miles, so not very old. There is another factor that came to mind when reading this thread: http://www.m3forum.net/m3forum/showthread.php?t=429288. The guy was having a similar problem and while the pump may be able to supply the fuel it looks like the lines may be too small and causing too much resistance/restriction of higher flow. Larger lines would actually decrease resistance and allow the pump to operate at a higher efficiency/rate. This along with an inline pump just to be safe might be another option. Now to the injection timing decreasing; if the ECU is seeing that the pump can't supply enough fuel at a certain point (because the lines are to restrictive, for example), then maybe the ECU is cutting the times because of the pressure drop. I'm not sure if this is a factor in the ECU's calculations, but possibly.

Either way, bigger lines and an inline pump can only help and aren't all that expensive. I'm just curious as to the the effects of doing so with the computer controlled FPR.

Here's what the guy, in the thread I linked to, did with his fuel system (he's running 12 psi though with meth, but experienced the same lean issues like I am before the upgrade).

42lb injectors
Aeromotive 340 sealth fuel pump (best choice)
larger fuel lines and relay.
Aeromotive fuel filter
Walbro inline fuel pump
AA bigger Fuel Rails
Aeromotive Fuel Press. Regulator (3bar)
50/50mix boost jucie Meth spary at 2.5psi to redline using .630cc jet

FPR gauge at idle reads 63-64lb. (with 60lb inejctors it should be at 43lb of pressure)

Quote:
Originally Posted by aerobod View Post
I believe that under WOT conditions the car should be running open loop and there should be no feedback from the O2 sensor (unless a non-OEM wideband sensor is being used).

If the data logging in this case is giving true information, the fact that fuel pressure doesn't move from 6 bar would indicate that fuel flow demand is being met. I would expect that if fuel demand couldn't be met, as the injector open time increases, the pressure could not be maintained due to flow limitations.

Rated, do you have any more data logging information available (such as fuel trim, throttle position, etc)? Also, I may have missed it, but does your installation make use of wideband O2 sensors, or is it using the standard OEM ones?
I don't have any other data logs at the moment, but I did record the driver input via pedal during the runs, which basically just shows I was on full throttle. I'm using the readings off of the OEM sensors.
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      12-16-2012, 01:31 PM   #98
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ohh god....

i really am going to have to do the fuel system upgrade i was hoping to avoid :-(

Rated, im with you on this one tho, if we start changing lines ect ect.... how much scope does our computer controlled FPR have??

id like to think the intank aero 340 intank would be more than enough for our usage. i wish someone just did an upgrade "kit" that had everything we need to do a fuelling upgrade.... i i'd love to get some proper specs on our fueling system in terms of pump flow ect ect.
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      12-16-2012, 03:25 PM   #99
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Wouldn't it be easier to ask VF engineering the afr map they put in your ecu?
I think they can just mail you a print/screenshot depending on software.

Then you know for sure if there's something wrong or that it's in the tune itself.
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      12-16-2012, 03:56 PM   #100
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I think AJ from ESS didn't do it because our fuel pump is controlled by the ECU and it will cost more in terms of R&D to tune it out as opposed to the E46 M3 platform.
Someone correct me if i'm wrong.
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      12-16-2012, 04:41 PM   #101
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Is it controlled (as in speed controlled) by the ecu?
I think the pressure regulator is passive with vacuum control?

Edit: WDS says so (pulse widh modulation) (still a vacuum pressure regulater is in place I think; there is a procedure with tools to check fuel pum[p pressure vs. pressure regulator pressure)
Control takes place via the diagnosis CAN, so maybe you can monitor it with inpa or progman (never seen it in inpa, but also never bothered to look ).
But I can't imagine the fuel pump not running @100% on WOT and +6500 revs.

Last edited by GuidoK; 12-16-2012 at 04:52 PM..
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      12-16-2012, 08:43 PM   #102
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Quote:
Originally Posted by GuidoK
Wouldn't it be easier to ask VF engineering the afr map they put in your ecu?
I think they can just mail you a print/screenshot depending on software.

Then you know for sure if there's something wrong or that it's in the tune itself.
The lambda setpoint during the runs were .83-.81 (12.2-11.9 afr) from 4600 to 6800 and .7 (10.3 afr) after that. That looks like what the tune was asking for even though it wasn't getting it.
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      12-16-2012, 09:31 PM   #103
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dirty fuel filter? small chance but.. who knows
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      12-16-2012, 10:11 PM   #104
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Quote:
Originally Posted by ZStig
dirty fuel filter? small chance but.. who knows
Very possible. It's probably worth replacing just in case.
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      12-16-2012, 10:23 PM   #105
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This thread makes me sad, I hope you find the culprit, and that its an easy solution
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      12-17-2012, 06:06 PM   #106
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More interesting info:

I graphed the injector duty cycles for runs 3-5:


Z4M VF570 duty cycles 3-5 by M detaR, on Flickr

They plateau at ~73-75%

Also, the M3 VF570 kit uses 52lb/hr injectors while the Z4M kit uses 41lb/hr injectors. This is most likely due to the different FPR, but still interesting.
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      12-17-2012, 07:46 PM   #107
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I not an injector guru, but shouldn't they be able to up the duty cycle to closer to 100??
If a fuel system upgrade is needed, it's not that much more money - relatively speaking of course.
Can't you bypass the factory PWM control, and run 100% all the time with an aftermarket pump / relay? That, a filter, fpr, and some nice lines - you'd be good to go - right?

I was hoping to hear that you talked to VF and they said .....
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      12-17-2012, 09:49 PM   #108
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Quote:
Originally Posted by Geauxkart View Post
I not an injector guru, but shouldn't they be able to up the duty cycle to closer to 100??
If a fuel system upgrade is needed, it's not that much more money - relatively speaking of course.
Can't you bypass the factory PWM control, and run 100% all the time with an aftermarket pump / relay? That, a filter, fpr, and some nice lines - you'd be good to go - right?

I was hoping to hear that you talked to VF and they said .....
85-90% duty cycle is about the highest you want to run for extended periods. The injectors should be able to handle much more fuel pressure though (via new lines and pumps), therefore reducing the duty cycles; if I wanted to up the boost later on.

VF should be contacting me tomorrow.
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      12-18-2012, 05:17 AM   #109
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I'm on bf.com monitoring your thread there too....I hate issues like this, especially after just being installed, so good luck to you.

With the idea of stock fuel lines being too restrictive...I'm not too sure you want to go that route just yet. The bottom line is, VF released this kit, ready to go as is. They would have noticed this issue and replaced the fuel lines too. This is a MAF based system, correct, and not a MAP based? If the engine runs lean at higher RPM, I'm either looking at some kind of air restriction going on, or perhaps the FPR/fuel pump cannot keep up and is failing.

The engine is seeing "x" amount of air, and is delivering "y" amount of fuel. "Y" is either correct according to the tune, according to what the ECU thinks the engine is seeing via the MAF, or what is limited by the fuel system.

Here is how I'd attack it and whenever I have problems on my turbo M3, this is my methodology:
1) Vac test.....usually, in boost, the engine will run rich because the accounted for air is leaking out in boost, but the fuel has already been provided...still, always check first and eliminate this as a potential issue...many people also want to assume away this problem...smoke test!
2) Fuel pressure check...what should it be idle, accelerating, in boost? Need to verify the fuel pump, FPR, injectors are all in compliance.

Good luck, and please let us know what you find out once this is resolved!
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      12-18-2012, 07:09 AM   #110
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Quote:
Originally Posted by aerobod View Post
I believe that under WOT conditions the car should be running open loop and there should be no feedback from the O2 sensor (unless a non-OEM wideband sensor is being used).
I think the precat O2 sensors are wideband, and that open-loop operation at WOT is a thing of the past for BMW's. I was under the impression that newer BMW's ran closed-loop all the time.

Quote:
Originally Posted by BMW Maniac
This is a MAF based system, correct, and not a MAP based?
I think the VF420 kit is MAF-based, and the 480/570 are MAF-less tunes.

Edit: I'm not where I heard this, and I'm reading different information on VF's website.
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