CTR L.Trim extremely rich

FK2 Civic Type R 2015-2017, FK8 Civic Type R 2017-2021, FL5 Civic Type R 2023+ and Integra Type S 2024+
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Hatchi
Posts: 4
Joined: Sat Dec 04, 2021 12:25 pm

CTR L.Trim extremely rich

Post by Hatchi »

Tl;dr -> Fuel trims are super rich. The hotter it gets outside, the richer the L.trim gets in the long term. Live at sea level, trying to get car to be holding stoichiometric because it seems to be struggling.

So I've been kind of dealing with this issue for a while. I've checked vacuum lines in where I'd think anything could have changed (that i've touched), it *could* technically be the MAF but i'm not so sure since it was happening also before removing and reinstalling it. Datalogs from colder months still show richness, but not as severe, start at -2% go to like -7% tops (the 12-4-21 is before intake install, having never touched any lines before that, 1-2-22 and beyond is post intake). I have the AFM correction for eventuri loaded onto the current tune. Nowadays its getting hotter, as you can see with the temps per datalog, and now my L.trims are starting at -8% and going to -14%, super duper rich.

Never modified these tunes on my own, but been studying up because I was planning on trying to refine the basemap tune for my specific car. That being said, I'm fully ready to accept the consequences with some mild direction. What troubleshooting can I do here, or what steps can I perform to correct the AFM/Fuel Trims.

One big question I have is, do I need a winter/summer tune? If I perform these corrections and get the car at atmospheric during summer, will the fuel trim be leaning out during winter and vice versa?

Tune: 93 w/improved throttle response, eventuri intake.
Attachments
FuelTestingThree4-30-22.zip
(2.57 MiB) Downloaded 58 times
FuelTestingTwo4-30-22.zip
(4.07 MiB) Downloaded 59 times
MeetDriveThere4-23-22.zip
(4.65 MiB) Downloaded 49 times
EventuriSecondDrive1-2-22.zip
(2.89 MiB) Downloaded 57 times
WeirdTrim12-4-21.zip
(1.69 MiB) Downloaded 70 times
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Hondata
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Re: CTR L.Trim extremely rich

Post by Hondata »

You need to tune for that intake - the AFM is over reading. I know that you have already selected the intake you are using, but still it needs to be done.

Honda has taken great care to make sure the air flow in the intake is linear past the AFM for different conditions. A good example is that the stock intake has indexed connections for both position and rotation. Any intake that does not do this will not be consistent.
Hondata
Hatchi
Posts: 4
Joined: Sat Dec 04, 2021 12:25 pm

Re: CTR L.Trim extremely rich

Post by Hatchi »

The datalog for 12-4-21 is before installing the intake (short drive so may not indicate too much, but it was still trending rich), does that one look particularly odd to you? I installed the intake on 1-2-22 and did 2 drives, the first AFM was all over the place, second much more stable and normal, basically flatlined at -8% after like 1.6V.

Also that's fine, I'd like to tune for the intake, where should I start with that? I'd like to learn this process, been through and around the documentation. Will modifying the lambda under 100% air charge give me the results I need? If so, which one? Just would like some guidance.
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