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Did I not tell you why it was running rich? Post another idle log when it’s warmed up.
 

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Discussion Starter · #22 ·
Did I not tell you why it was running rich? Post another idle log when it’s warmed up.
You did, indeed and I am really happy I can count on the GTR community! I am waiting for Cicio to get back to me and comment on adjusting IPW and STFT.

Strange thing is ... when we first tuned the car, it had better AFR values (much closer to Target AFR). Now even if we go back to previous versions of the map it still is very rich...

Attaching new log.
 

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You did, indeed and I am really happy I can count on the GTR community! I am waiting for Cicio to get back to me and comment on adjusting IPW and STFT.

Strange thing is ... when we first tuned the car, it had better AFR values (much closer to Target AFR). Now even if we go back to previous versions of the map it still is very rich...

Attaching new log.
So again, this appears to be a tune issue so Cicio needs to address the inability to hit targeted AFR first to determine whether or not it is contributing to your stalling issue. The first thing I notice is the STFT is still constrained to -10% / +20% vs +/- 20%, but the log doesn't tell me why this is the case. You are correct that the AFR is closer to target, but it is still running too rich. Based on this change, I can only assume the VE table needs to be adjusted until STFT is within 5%.

Rectangle Font Parallel Slope Pattern



Per my previous post, 1650cc injectors idle just fine on my EVO with ~1.24ms of IPW and I estimated they would do the same on the GTR with about 1.46ms IPW. If I look at the idle portion of your log I can see it is now running consistently lower than 2.00ms, which is why AFR is closer to target. There are portions of the log where IPW randomly dips to ~1.4ms IPW and AFR reaches target, which suggest its the VE table. Based on this limited data, the IPW to maintain idle may actually be close to what I run on the EVO at 1.24ms. The other comment I will make is that I doubt you need to target 12.5:1 AFR for idle stability so probably 13.5:1 would work just the same. If the cams are GSC S2 equivalent or smaller and the head is unported, then likely it will have good idle stability at stoich. The last comment is you don't need to run any intake cam timing at idle to gain stability, but I suspect its running 9deg because the TPW is reading higher than it would normally because the tune is off. Look at the graph below and you can see when IPW is around 1.4ms it reaches AFR target.

Rectangle Slope Font Parallel Plot
 

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Just recalled. My trans issue. I believe it could be seen when logging TCU via ecutek. 2 sensor values indicating gear. If they are not in sync. Chances are you have a broken cog.
You could also change drop the transbellypan and inspect and/or change transmission oil and look for metallic flakes. In my case we found cogwheel parts in the pan.
 

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We know the car is running rich because the IPW is excessive so if the TPW correlates to the IPW, that could be the problem. Clutch Torque is a function of TPW so when it increases it causes the clutch pressure to increase, which couples the trans to the motor. If you can provide a log and include TPW "Theoretical Pulse Width" we can see if that is potentially contributing to the stalling.
 

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Discussion Starter · #27 ·
Update
Several versions of the map later, things are starting to look much better.
Normal driving appears to be okay. Still sorting out some of the idling.
 
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