Initial Tune cranks over, not run well 240sx KA-T

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EnnEssEnnKAT
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Initial Tune cranks over, not run well 240sx KA-T

Post by EnnEssEnnKAT » Tue Aug 01, 2017 2:42 pm

Hi all, I was able to get my nistune communicating and set up on my ECU! Check!

Now that I have started logging I am trying to understand my cold start problem but nothing jumps out to me in the log. Complete lack of power, very hard to get the car to start. I adjusted MAF for my Z32 and injector k-constant to account for my 550 injectors. That's about it so far. I have a type 3 board and here's what I got for my first log of the car eventually cranking over to a rough idle for a few seconds.

Does anything stand out to anyone about what my problem might be? I need to read the tuning by example more..Thanks!
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Joe_TestStart5_2017-07-31_2330_01.csv
(20.37 KiB) Downloaded 74 times

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Re: Initial Tune cranks over, not run well 240sx KA-T

Post by Matt » Tue Aug 01, 2017 9:56 pm

Please post the tune file too

EnnEssEnnKAT
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Re: Initial Tune cranks over, not run well 240sx KA-T

Post by EnnEssEnnKAT » Tue Aug 01, 2017 11:13 pm

I've attached the tune file. The previous owner/person who got the tune was running a similar setup. I tried starting as it was, but had even worse luck. Adjusting my K value seemed to help it turn over more frequently.
Thanks!
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Saved_MyECUw_Nistune.bin
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EnnEssEnnKAT
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Re: Initial Tune cranks over, not run well 240sx KA-T

Post by EnnEssEnnKAT » Wed Aug 02, 2017 4:12 am

Here's a better, 30+ second log where I actually got it to run steady but it would not idle on its own. By the way, this program is awesome!
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Joe_TestStart6_3.csv
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EnnEssEnnKAT
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Re: Initial Tune cranks over, not run well 240sx KA-T

Post by EnnEssEnnKAT » Wed Aug 02, 2017 4:14 am

Here's also the initial tune I got when I purchased the ECU, and then downloaded it immediately. Guy was using a blow-through MAF setup versus me running it on the turbo intake about 18 inches away.
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Saved_Initial.bin
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EnnEssEnnKAT
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Re: Initial Tune cranks over, not run well 240sx KA-T

Post by EnnEssEnnKAT » Wed Aug 02, 2017 12:53 pm

I made a little progress tonight and basically started "from fresh" with an s13 ka24de stock tune, added z32 MAF, scaled injectors to the 520cc I have via K const, hooked up my wideband to see where I was at, disconnected the o2 sensor, and went and started the car.

The car starts but still a bit stumbly. The AFRs were 18+ so that's obviously an issue. The car would rev a bit but being very lean I called it after 20s.

Here is that tune and log.
Attachments
Joe_TestStart6_11.csv
(158.12 KiB) Downloaded 84 times
Trial_Tune_GoodStart.bin
(32 KiB) Downloaded 71 times

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Re: Initial Tune cranks over, not run well 240sx KA-T

Post by Matt » Fri Aug 04, 2017 12:41 am

Hold vehicle at cruise and increase your injection multiplier until around 14.7:1

Also make sure you read our tuning guides

EnnEssEnnKAT
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Re: Initial Tune cranks over, not run well 240sx KA-T

Post by EnnEssEnnKAT » Fri Aug 04, 2017 11:23 pm

Thanks for your help Matt. The above is my very next step. I was battling a rough start/idle and I learned the injector adapters were not fully connected, actually the pins got pushed out but they were clipped/seated. Two of them were like this..

Anyways I am running much better now, the idle is good and I have checked my AFRs with a wideband at idle and highway cruise and see they are much better. It will need some minor adjustments to the fuel map.

I am seeing a 13-14.0 AFR when on the highway, and with little throttle it will drop to 11.0 and fluctuate between there to 12.5:1. I think my tune might be a little rich. I am going to set up the AFR tracer and try out auto tune or tweak the AFR myself but will definitely read up more on the training notes. Thanks for the help thus far.

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Re: Initial Tune cranks over, not run well 240sx KA-T

Post by Matt » Wed Aug 09, 2017 12:44 pm

Definitely use the tracer to see where it is at and then make adjustments from there. Or use the logs to view. Only use the autotuner if you know what you are doing otherwise it will mess up your map

Throttle enrichment tables will add more fuel on acceleration initially so keep that in mind

EnnEssEnnKAT
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Re: Initial Tune cranks over, not run well 240sx KA-T

Post by EnnEssEnnKAT » Wed Sep 20, 2017 11:24 am

Small update:
I have been doing a good bit of logging and am creeping up in RPM and timing. However I seemed to have run into a misfire issue as I start to go higher RPMs, particularly full throttle. It feels like an ignition cut but I am not sure. I was thinking of replacing my ignition wires but first I wondered if any clues could be seen in a log during the misbehavior. I have a good small spark plug gap and plenty of fuel pressure, I checked those first, but I have no idea yet. Any help is appreciated!
Attachments
t10.bin
tune test10
(32 KiB) Downloaded 69 times
t10_3.csv
tune 10 log
(44.81 KiB) Downloaded 63 times

EnnEssEnnKAT
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Re: Initial Tune cranks over, not run well 240sx KA-T

Post by EnnEssEnnKAT » Sat Sep 23, 2017 2:09 pm

EnnEssEnnKAT wrote:Small update:
I have been doing a good bit of logging and am creeping up in RPM and timing. However I seemed to have run into a misfire issue as I start to go higher RPMs, particularly full throttle. It feels like an ignition cut but I am not sure. I was thinking of replacing my ignition wires but first I wondered if any clues could be seen in a log during the misbehavior. I have a good small spark plug gap and plenty of fuel pressure, I checked those first, but I have no idea yet. Any help is appreciated!
Everything is fine now, was either my fuel filter, plug wires, or ignition coil ground

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Re: Initial Tune cranks over, not run well 240sx KA-T

Post by Matt » Mon Sep 25, 2017 6:08 pm

oh, at least its sorted... not a tuning issue?

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