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350z turbo idle drop and accel stutter


PopesSimpleSpares

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Just chasing an oil leak today so don't think i'll be able to get a log of the idle issue happening just yet.

I noticed just now when looking at the log that the APS drops when it stutters. Might the factory traction control be causing some conflict here? 

What would you expect normal accel fuel to be? Have attached the map, not quite sure where I should be changing it.

thanks

350z 28april IAT.pclx

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Start with the idle settings changes in green below.  The base position table looks like it probably needs work, so log a cold start and allow it to completely warm up then use the logged TPS to aid filling out the base position table. 

WbAYWoC.png

 

For the accel fuel try these changes:

8Na08wY.png

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Settings all changed to reflect suggestions, did a cold start warmup and changed the idle base position table to the logged values - I assume it's fine to just copy the value from 20 through to -20 and from 90 through to 120.

Already can notice the idle catches a lot better. Will take it for a drive in the morning to check how the acceleration has changed.

Thanks 

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Driven this morning, still stalling, heres a couple logs and the updated tune. I'm still not sure what's causing it to drop out. seems to happen only when its warming up.

Thanks

PC Datalog - 2023-05-24 10;23;12 am stall after.llgx PC Datalog - 2023-05-24 10;25;17 am stall 2.llgx 350z 23 may Idle setup.pclx

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I just spotted the e-throttle target table has non-zeros in the top row also so that is not ideal.  I have made some further changes as well as those already suggested above in the map that is attached to this post.  Load this in, then you will have to log a cold start/warmup and adjust the base position table again but I think this should be a better starting point.  

350z 24 may Idle setup.pclx

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Mostly looks like the basics are in the ballpark now, you will now need to tune the dash pot function so it enters into idle control nicely.  This varies a lot from engine to engine so you just need to experiment live to get that working nice.  

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Hey so i got the dashpot setup so it would consistently catch the idle and after leaving the car for a couple hours it drove great with no issues. When I started the car after it being stopped for 5 minutes I got these 2 logs. Where would I make a change to prevent this? 

thanks

PC Datalog - 2023-05-25 2;25;55 pm after dashpot.llgx PC Datalog - 2023-05-25 2;27;05 pm compare.llgx

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Had a yarn to a mate and he pointed out the switchover from the main ignition table to the idle ignition was quite harsh. I've retarded the ignition table above -20 a bit, set the idle ignition target to 15 and reduced the switchover rpm to 500 above target. Will test it in the morning but does this updated map look like it might respond a bit better?

350z 25 may ignition update.pclx

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19 hours ago, PopesSimpleSpares said:

When I started the car after it being stopped for 5 minutes I got these 2 logs. Where would I make a change to prevent this? 

The main difference between those 2 logs is you have AC running in the second one, so you need more AC offset - and usually a bit of AC idle up is used also.  

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  • 2 weeks later...

I've been going a bit in circles trying to fix a couple things. first the idle keeps dropping out as it warms up around the 70 degree area, and off idle there's a new hesitation that I can only guess is being caused by the ignition setup. no longer having issues with the AC loading. The log I've attached from today is just the hesitation off idle as I didn't have the laptop hooked up when it was having issues. The current map is basically all the updates you've given plus some dashpot and the idle base position table setup - no changes to ignition.

7 june changes.pclx

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1 hour ago, PopesSimpleSpares said:

and off idle there's a new hesitation that I can only guess is being caused by the ignition setup.

Yes, I would say this is likely, you have 23deg around the idle area of your main ignition table that dips to 12deg deg when you initially open the throttle.  The lambda is not working in that log though so I cant say it is only due to ignition.  

VwEu6Mn.png

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