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Old 06-04-2012, 01:40 PM   #21
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Default Not an ignition problem...

So I think I did the ultimate test, if it is ignition system related...

I swapped in my DIYPNP and did a run with the EBC:

Screenshot of the run with the MS3/MS3X



Ends at 5800 rpm with a hell of AFRs...

Screenshot with the DIYPNP only some minutes later,



Perfectly clean up to 6800 rpm with no AFR problems whatsoever...

Now what could cause this inside the MS3...?
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Old 06-04-2012, 01:56 PM   #22
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What do you see on the MaxiGauge, re: AFR?

Do you have an MBC to try with the MS3?
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Old 06-04-2012, 02:14 PM   #23
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Quote:
Originally Posted by Reverant View Post
What do you see on the MaxiGauge, re: AFR?
Same as in TunerStudio... Getting really lean, AFR going to 16 and higher (for a splitt second...and I let go off the gas, because I need my engine.

Quote:
Originally Posted by Reverant View Post
Do you have an MBC to try with the MS3?
No, unfortunatly not...
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Old 06-04-2012, 02:23 PM   #24
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Get a cheap one then.
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Old 06-04-2012, 02:36 PM   #25
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Would you please explain, what this would be helping me? I know that the EBC with the diypnp works settings are the same...
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Old 06-04-2012, 02:45 PM   #26
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I can't tell from the logs, but do you hit the same amount of boost with the MS3 with and without the EBC when the problem occurs?
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Old 06-04-2012, 02:51 PM   #27
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With the MS3 I can run wastegate pressure at ~145kPa without a single glitch, the MS3 and DIYPNP EBC runs are both equally at 170kPa - DIYPNP up to 6.8k rpm at AFRs~11.3, the MS3 starts to go strange at ~ 4.5-5 k rpm...
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Old 06-04-2012, 03:50 PM   #28
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Use an MBC with the MS3 to reach 170kPa without actually flowing current through the EBC and the MS3X - this will tell quite a story.
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Old 06-04-2012, 03:52 PM   #29
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im running 205kPa with the MS running boost control, but not through the expander card. It's possible it needs the same flyback mod as the idle and vvt outputs do.
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Old 06-04-2012, 04:08 PM   #30
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I have a flyback diode added directly at the solenoid connector - shouldn't this be enough?
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Old 06-04-2012, 04:10 PM   #31
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yeah it should. n/m then.
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Old 06-04-2012, 04:23 PM   #32
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I might build the boost control circuit at the mainboard, what is the easiest way to do this...?
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Old 06-05-2012, 03:39 AM   #33
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As the problem very clearly sits inside my MS3 I went and had a look at the connections to the MS3 / MS3X. I might have found a culprit...

That is the connection of the MS3X to the boost control - you can see a little splice of wire going very near to the next pad - it might even have touched.

I went and resoldered some funky looking wires - we'll see if this brings us somewhere... (I will try to test at the jimstim...)

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Old 06-05-2012, 03:20 PM   #34
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Default injector dead times again...

So it was not the solder-points or the little splice of wire...

I did another test today:

With my actual MSQ I get the same thing again:


See how the AFRs go deadly lean after 5800rpm, although the GVe goes higher and higher, also the AFRs start to fluctuate and at 6k rpm the AFRs start to go completely shaky... (VEtable going from 100 at 500 rpm up to 110 at 6000 rpm)

Now I tried another test with the deadtime set to 1.185 - my previous setting at the DIYPNP



See how the AFRs just start to lean out only a little when at the same time the GVe drops quite a bit due to my old VEtable... no rpm fluctuations, no AFR fluctuations up to ~6.3k rpm where I stopped because the AFRs got a little too lean due to my VEtable going down from 85 to 80.

I also noticed that my dutycycle with the 0.75ms deatime goes up to 77.5% at ~6.200 rpm, where the dutycycle with the 1.185ms deatime is only ~60%.

Gonna have to take another run tomorrow with a changed VEtable and the 1.185ms setting for deadtime. (I did a VEanalyze with the Megalogviewer and my log for this deadtime and the VE was brought up to ~86.5 at the leaner getting spot ~6k rpm/170 kPa, which seems about right)

Edit: Just had a look - both runs were 3rd gear..

Thoughts?

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Old 06-07-2012, 11:47 AM   #35
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Injector dead times also ruled out in the equation...

I don't know any further anymore...

I am going with one more test with injection timing all set to 370 which should equal the DIYPNP setting I had with -350.

Apart from that my next steps would be to try a different MS3X output to drive the boost control or building the boost control circuit to the mainboard.

@Brain (and the others of course) what Diode should be used for the boost control (I used a 1N4001 I had from my builds... - must this be a 1N4002?)
I have the diode directly at my solenoids connector - when I add the diode add the DB15 on my MS3 (where my boost control line goes out) can I connect it to any +12V source? (I have a +12V going to the ZT-2 WB also at the DB15...)
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Old 06-07-2012, 11:51 AM   #36
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any direct 12v source, nothing behind the diodes and caps on the circuit for the 5vregulator.

and yes n4001.
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Old 06-07-2012, 12:10 PM   #37
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which other output on the MS3X would you recommend for testing purposes for the boost control?
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Old 06-07-2012, 12:13 PM   #38
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nitrous 1, nitrous 2, or vvt
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Old 06-08-2012, 04:21 AM   #39
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Still trying to wrap my head around the problem - I stumbled over this picture:



As I did my wiring according to Frank's instructions - my MS3X has NONE of the ground connections to engine ground. (pins 2/3/8/12/17) Could this have anything to do with my problem?
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Old 06-08-2012, 04:48 AM   #40
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Oh boy. Definitely the grounds.
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