MS3 dropping AFR value at ~4700rpm

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MS3 dropping AFR value at ~4700rpm

Postby Snake____1 » Thu Dec 28, 2017 5:39 pm

Hi,

So currently I have a problem with a BMW M52TUB25 "dual vanos" engine running on MS3 1.5.1...

I have attached the plot from the DynaPack and MSQ. Issue is at around 4400-4800rpm the AFR value drops down below 10 and engine suffers enormous powerloss when boost comes on.

I have tried increasing Dwell without luck, and specifically removing a little fuel at specifically 4700rpm only to get a great spike before drop in AFR value.

Running engine without VANOS connected.
Specs are SuperT70 turbo, Siemens 850cc high-Z injectors and MS3 V3 ECU.
MS3 specs: Hijacked the 14CL36 ignition drivers from OEM ECU, running IRLR3103 mosfets for each injector MS3X style.


Tips and tricks are welcome!
Attachments
IMG_20171227_205513-min.jpg
DynaPack
IMG_20171227_205513-min.jpg (779.29 KiB) Viewed 135 times
M52TUB28_Glenn.msq
Tune
(275.5 KiB) Downloaded 10 times
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Snake____1
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Re: MS3 dropping AFR value at ~4700rpm

Postby Matt Cramer » Fri Dec 29, 2017 6:50 am

Can you also post up the ECU's data log of what is going on?
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Re: MS3 dropping AFR value at ~4700rpm

Postby tryingbe » Fri Dec 29, 2017 8:46 am

How much boost were you running?

Your fuel and ignition map looks really odd to me.
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Re: MS3 dropping AFR value at ~4700rpm

Postby billr » Fri Dec 29, 2017 4:00 pm

Note that the req_fuel is way off; that's why the VE looks so strange.
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Re: MS3 dropping AFR value at ~4700rpm

Postby Snake____1 » Thu Jan 04, 2018 7:48 am

Soo... After an excruciating fault finding mission I figured out that the CAM sensor was dropping out at 4700RPM.

For the guys pointing out that the VE table looks wierd, the Req.Fuel was wayy off and the Injector Dead Time was also set way to high. But thanks!
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