CA18DET deceleration issues

[Matt]

Fuel cut table values are higher than recovery values (the table names were wrong way around)

When the RPMs drop the fuel is cut for a short period of time, and then it resumes injection at the recovery point.

[mattlovo]

Fuel cut table values are higher than recovery values (the table names were wrong way around)

When the RPMs drop the fuel is cut for a short period of time, and then it resumes injection at the recovery point.

Thanks Matt.
Perhaps I can try readjusting again to see if I can smooth out the deceleration.

So logically, the fuel cut table values should be higher and recovery rpm lower ? Correct me if I am wrong.
Still new to all these tuning-nologies.

Seems like a light weight flywheel really needs a fine tune for those of us who put in one without knowing that it affects the way a car engine slows down and idle etc

[Matt]

Yes the fuel is cut on decel (cutting on the way down... high RPM until recovering at lower RPM)

[mattlovo]

Hi Matt, need your help on this.
I have been playing around with the Fuel Cut and Recovery function in the JDM S13 CA18det map. I have set both to 6000rpm.
The car does not seem to react to this after uploading and burning the map in. 1st gear moving up to 3500rpm and letting off the gas would have the AFR go to 22.0.

Previously, I have tried to raise the cut and recovery to 3500ish but it did not work. Hence I tried to never have it cut fuel unless above 6000.
TPS is new and does light up showing TPS on when foot off the gas.

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Lastly, I tried to alter the Idle Deceleration Timing, which ended up with a weird graph.
Not sure why it spiked up to the sky.

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[Matt]

Please email the tune and matching log file showing the AFR on decel (and associated consult data) so I can look into it further

Not sure with the decel timing table. Some tables have +128 offset (filtered) but you are viewing the table as raw, so need the file to compare against the factory one

[mattlovo]

Hi Matt I am unable to PM u the map in the forum.
Is there another way ?

[Matt]

Yes email... info@nistune.com

[mattlovo]

Hi Matt,
I have sent the file last Friday. Do let me know if you find any thing in it.

[Matt]

I've been away over the weekend so just catching up on the forum now.

Lastly, I tried to alter the Idle Deceleration Timing, which ended up with a weird graph.
Not sure why it spiked up to the sky.

This graph has an offset of 16. When you drop the table values (which are timing BDTC) below 16 it will then 'wraparound'

So you cannot set the 'raw' values lower than 16 (which is 0 deg BDTC in 'filtered view')

Fuel cut/recovery tables are for a small period of time of fuel cut. For example, the original tables are say between 1200-1100rpm (at 80degC) that it will cut fuel and then recover.

So you are increasing both of these tables (including the recover) so that it does not cut fuel? What is the cause for the overfueling? I really need a log file (with AFRs) so have a full picture what is going on. Rest of file seems ok

[mattlovo]

Hi Matt,thanks for looking thru it.
I am trying to raise the fuel recovery and fuel cut to compensate for the light weight spec flywheel.
Car tends to stalls out when clutching in and off the gas.

Raising the fuel cut to insane rpm range and fuel recovery did not have any reaction.
Hence I am puzzled as AFR would show 22.0 when decelerating at various range of rpms

[mattlovo]

Hi Matt,
I got the timing values solved and understood what you meant.

But as for the fuel cut/recovery, it does not seem to change anything significantly.
let's say fuel cut 3500rpm and fuel recovery 3200rpm,
I am off the gas at 3500rpm, afr goes to 22.0 but doesn't recover to 14.7 at 3200rpm until it touches 1000rpm.

[Matt]

Please send a log file showing this issue with AFRs to investigate further

Those fuel/cut recovery tables may not be able to related to the fuel cut you are currently seeing, which is why adjusting them makes no difference

[mattlovo]

Understood.
could it be a possible hard coded fuel cut /recovery as seen in Hondatas?

I am still unable to get the AFR to communicate with the laptop at the moment due to windows 10.

[Matt]

I've not looked into fuel cut in close detail. Normally it only cuts between the ranges in those tables. I would need the log to check out the problem to see where your cut is occouring

[mattlovo]

Hi Matt noted.

In short I still can't get a log with AFR values in it.
Tables for fuel cut/recovery have no impact on deceleration when I change them to max rpms.

Timing table for deceleration does work.
Will try to get a driver for the wide band to work again.

Meantime, I will try to raise Min TP to see if it helps.