CA18DET deceleration issues

Nistune topics specific to the 6802 cpu

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raddy
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Re: CA18DET deceleration issues

Post by raddy » Sun Nov 12, 2017 7:18 am

table that I mentioned is called idle/deceleration vs RPM (TPS ON) , do not change other timing tables for off throttle rpm management.

mattlovo
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Re: CA18DET deceleration issues

Post by mattlovo » Mon Nov 13, 2017 2:41 pm

Hi Raddy,
I'll check it again.

Kinda messed up abit of the tables which led to not so ideal AFR of 14.
Thanks for the tip.

Has anyone else tried to compensate for a lightwheel flywheel?

mattlovo
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Re: CA18DET deceleration issues

Post by mattlovo » Tue Nov 14, 2017 1:09 pm

Right, so there is the values for Idle/Decceleration when TPS is on.
Moved the timing up for rpm range 600-1200.
Question: Won't I have to try increase it up the range as the car is decelerating?

An observation: When my car is started up, she revs fine, doesn't dip when the temps are cold, but once it hits warm up temp of 60 ish, that smoothness is gone.
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mattlovo
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Re: CA18DET deceleration issues

Post by mattlovo » Thu Nov 16, 2017 12:54 pm

Hi Matt,
quick question on Fuel Cut and Fuel Recover.

For the Fuel Cut, setting the value (RPM) at which fuel is cut when it reaches that RPM value ?

Fuel Recover, as I read in the manual, points at the rpm which the fuel injection resumes.
Would raising the Fuel recovery rpm mess up if the Fuel Cut rpm is lower? or vice versa?

Sorry for the silly questions as I am trying to get my head around the parameters of the tune and jargons.

Matt
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Re: CA18DET deceleration issues

Post by Matt » Thu Nov 16, 2017 2:05 pm

Don't confuse TP (load cut) aka boost cut (which cuts fuel on acceleration) with Fuel cut/recovery

Fuel cut/recovery do a small amount of fuel cut on deceleration (when TPS idle) to avoid injecting when throttle released.

For example @ 80degC Ctemp: 1200rpm cut to 1100rpm recovery

Just noticed table names backwards so will fix these. Normally do not need to alter these tables

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Re: CA18DET deceleration issues

Post by Matt » Thu Nov 16, 2017 2:06 pm

Question: Won't I have to try increase it up the range as the car is decelerating?
Normally we dont need to change this table. Only used on decel

mattlovo
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Re: CA18DET deceleration issues

Post by mattlovo » Thu Nov 16, 2017 4:43 pm

Thanks Matt.
Seems abit clearer now. I tried to adjust fuel recovery to a higher RPM so as to get it to catch the engine from choking down to 600 rpm before it slowly bounces back up due to that light weighted flywheel in the car.

As for fuel cut, I left it much alone for the moment as I have yet to mess with it to see if the tech can compensate for a light weighted flywheel.

Regarding the tables, the next update would fix them from ascending order?

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Re: CA18DET deceleration issues

Post by Matt » Fri Nov 17, 2017 9:55 am

only swap the table names in next update

Timing ascending values are nissan defaults in that table. Right click and 'filter' the values to see BDTC

mattlovo
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Re: CA18DET deceleration issues

Post by mattlovo » Wed Nov 22, 2017 5:58 pm

Thanks Matt, will run the next update when I get the laptop into the car again.
Will try to adjust the fuel recovery again.

Raddy, I have advanced the timing for the deceleration vs rpm map. Seems to have improvements over previous setup but not 100% on the issue.

Any idea how far advanced can I go before I start having issues in the deceleration ?

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Re: CA18DET deceleration issues

Post by Matt » Thu Nov 23, 2017 5:20 pm

Never needed to adjust timing tables on decel (only accel) so I would keep decel timing in the similar range to accel

mattlovo
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Re: CA18DET deceleration issues

Post by mattlovo » Fri Dec 15, 2017 12:57 pm

Matt wrote:only swap the table names in next update

Timing ascending values are nissan defaults in that table. Right click and 'filter' the values to see BDTC
Hi Matt,
has the table name swap been implemented?

Just to clarify, the 2 tables you mentioned are the Fuel Recovery and Fuel Cut tables?
Meaning their names are wrong?

I still can't get the car rpm to drop and stop at 900 rpm nicely without a small amount of dip to 650-700rpm below it slowly bounces back up.

Got my AFR linked to the laptop and will do a log soon.

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Re: CA18DET deceleration issues

Post by Matt » Fri Dec 15, 2017 2:43 pm

See if the drop is AFR or timing related in your logs

Yes names were swapped around the last release this week

Torque
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Re: CA18DET deceleration issues

Post by Torque » Fri Dec 22, 2017 8:15 am

Matt wrote:See if the drop is AFR or timing related in your logs

Yes names were swapped around the last release this week
Was that also mixed up in Type 2? (Z32?)

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Re: CA18DET deceleration issues

Post by Matt » Fri Dec 22, 2017 11:20 am

The change was only made to the CA18DET address file. Just checked Z32 tables and those are correct as is. Fuel cut should be higher than recovery

mattlovo
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Re: CA18DET deceleration issues

Post by mattlovo » Tue Jan 02, 2018 8:03 pm

Matt wrote:Don't confuse TP (load cut) aka boost cut (which cuts fuel on acceleration) with Fuel cut/recovery

Fuel cut/recovery do a small amount of fuel cut on deceleration (when TPS idle) to avoid injecting when throttle released.

For example @ 80degC Ctemp: 1200rpm cut to 1100rpm recovery

Just noticed table names backwards so will fix these. Normally do not need to alter these tables
Hi Matt,
downloaded the latest nistune version.

Did like to clarify what does it mean by the table names backwards?

Does it mean fuel cut and fuel recovery tables names are swapped around?

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