Rb25det turn poor afr after 6500rpm

Nistune topics related specifically to the 6303 cpu

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stinger
Posts: 6
Joined: Mon Jun 28, 2010 12:14 am

Rb25det turn poor afr after 6500rpm

Postby stinger » Wed Apr 25, 2018 7:15 am

Hi,

Need help for my problem.

On full throttle, AFR run good until 6500rpm: 11,5AFR
But 6500rpm to 7400rpm, AFR go poor: 12,5AFR

My log show that injection-time decrease after 6500rpm. TP (Load) decrease too..
6500rpm to 7400rpm, MAF stay at 50268value.

If you have any ideas...

My setup:
Rb25det S2
Maf Z32
Injector deatschwerks 550cc
GT3076R 15psi

Thanks
Attachments
NIStune_2018-04-24_1259_11.csv
(20.44 KiB) Downloaded 18 times

iyarovoy
Posts: 39
Joined: Wed Dec 23, 2015 3:47 pm
Location: California

Re: Rb25det turn poor afr after 6500rpm

Postby iyarovoy » Thu Apr 26, 2018 3:20 am

You need to post your tune as well (.bin file from nistune) such that we can see all your parameters at work instead of analyzing the Excel spreadsheet.

stinger
Posts: 6
Joined: Mon Jun 28, 2010 12:14 am

Re: Rb25det turn poor afr after 6500rpm

Postby stinger » Thu Apr 26, 2018 3:51 am

There is my tune.

I noticed in Throttle Enrich 1/2/3/4 all values are at 255... It is possible to create problem?
I can't test today with standard values.
Attachments
RB25DET Test 5 pour 1bar .bin
(32 KiB) Downloaded 32 times

Matt
Site Admin
Posts: 7980
Joined: Sun Jan 29, 2006 1:45 am
Location: Adelaide, Australia
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Re: Rb25det turn poor afr after 6500rpm

Postby Matt » Fri Apr 27, 2018 7:28 am

Put the throttle enrich tables to normal. However I don't think it will be related to this issue

Below log shows the problem:
tracerb25.PNG
tracerb25.PNG (92.94 KiB) Viewed 482 times


You can see that RPM keeps increasing, but MAF load measured (blue) stops increasing at the same rate, and then TP calculated load (grey) and injection time (orange) start dropping off

The only way to stop it leaning out here is to add more fuel to the affected part of the fuel map, so the orange line stays up, despite TP dropping. I cannot think of any other way around this

stinger
Posts: 6
Joined: Mon Jun 28, 2010 12:14 am

Re: Rb25det turn poor afr after 6500rpm

Postby stinger » Mon Apr 30, 2018 5:04 am

Thanks for your answer Matt.

Sans titre.jpg
Sans titre.jpg (236.98 KiB) Viewed 424 times


It is better but it's not beautiful :?

Do you think I can edit VQ Map on the column concerned to increase the value?

Matt
Site Admin
Posts: 7980
Joined: Sun Jan 29, 2006 1:45 am
Location: Adelaide, Australia
Contact:

Re: Rb25det turn poor afr after 6500rpm

Postby Matt » Tue May 01, 2018 10:14 am

Normally I see that type of map when we see fuel pump issues (fuel pressure drops) but in this case we know the MAF load is dropping

You can also increase the VQ map to push the TP higher, but it is not necessary if the above fuel map does the same job


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