-10% Short trim and Long trim Fuel Idle times?

randylauj94

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Hello all,

Just wanted to get allittle more insight. I'm currently using TSP Stage 1 with Mimishmoto SRI. My L.Trim is at -10% idle and S.trim is at -7%. I seen the Short trim as low as -14% and Long trim at -14%. Was wondering if something else is going on?

I flashed to hondata +6 with Mishimoto SRI and now Idle im between -3% - 0%. Is it just the tune? Thank you in advanced.

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I also find TSP1 runs rich on my car. What fuel are you using?
 

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Hey, I'm using 93 octane!
When I was running Shell or Esso 91 my LTFT was closer to -10. Those fuels are 0 ethanol IIRC. On PetroCan 94 my LTFT dropped immediately to about-4. I believe that fuel has some ethanol. So maybe its a combination of the tune running rich for our specific cars + our climate + the fuel ethanol content.
 
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randylauj94

randylauj94

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When I was running Shell or Esso 91 my LTFT was closer to -10. Those fuels are 0 ethanol IIRC. On PetroCan 94 my LTFT dropped immediately to about-4. I believe that fuel has some ethanol. So maybe its a combination of the tune running rich for our specific cars + our climate + the fuel ethanol content.
That makes sense a bit. It has been quite hot here in the east coast recently. I'll monitor it more while I"m on the hondata flash. Currently using Wawa 93. No Shell near me. I'll try a different 93 possibly. thank you!
 


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Has your idle changed at all since doing your intake?

Check if you have a vacuum leak after the MAF when you installed your intake. Also check the hotwire in your MAF sensor. Very possible something got left loose during installation and is introducing new air that MAF is not picking up, leading to the system to leaning out.
 

Ben0012

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Has your idle changed at all since doing your intake?

Check if you have a vacuum leak after the MAF when you installed your intake. Also check the hotwire in your MAF sensor. Very possible something got left loose during installation and is introducing new air that MAF is not picking up, leading to the system to leaning out.
it’s taking fuel out, which is a rich condition. Not lean.
 

fenix-silver

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I could see the SRI contributing to the fuel trims as well as you're pulling a lot of hot air. I noticed w/ my CAI my fuel trims improved over the stock intake during the very hot summer we've been having. On the stock intake I'd see -7/-8 LTFT, but after switching to the 27won I believe the worst I've seen in -4. During the winter both the OEM and 27won hover right around 0. Obviously the MAF housing itself has an effect on the fuel trims, but I think in this case it's primarily from the CAI pulling in cooler air than before.
 
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randylauj94

randylauj94

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Has your idle changed at all since doing your intake?

Check if you have a vacuum leak after the MAF when you installed your intake. Also check the hotwire in your MAF sensor. Very possible something got left loose during installation and is introducing new air that MAF is not picking up, leading to the system to leaning out.

Honestly I have not looked at fuel trims when I had the stock intake, my mistake on that part so I cannot give you an accurate answer on that. I'll recheck my connectors and make sure everything is snug.
 
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randylauj94

randylauj94

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I could see the SRI contributing to the fuel trims as well as you're pulling a lot of hot air. I noticed w/ my CAI my fuel trims improved over the stock intake during the very hot summer we've been having. On the stock intake I'd see -7/-8 LTFT, but after switching to the 27won I believe the worst I've seen in -4. During the winter both the OEM and 27won hover right around 0. Obviously the MAF housing itself has an effect on the fuel trims, but I think in this case it's primarily from the CAI pulling in cooler air than before.

Got cha! I can see that being the case. In PA, the summer has been so brutal so just regular cruising, I notice the difference.
 


fenix-silver

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Got cha! I can see that being the case. In PA, the summer has been so brutal so just regular cruising, I notice the difference.
Didn't even notice that you were in PA as well. Yeah, it's been brutal. If the fuel trims improve as the cooler weather sets in, that should answer your question.
 

PowerPerLiter

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Put the factory intake back on with the tsp and recheck. Intakes cause this issue.
 
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randylauj94

randylauj94

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Put the factory intake back on with the tsp and recheck. Intakes cause this issue.
You think I need maf scaling if intakes are throwing the numbers off?
 

PowerPerLiter

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You think I need maf scaling if intakes are throwing the numbers off?
Yes. I ran the exact same intake. You could rescale the maf but take it from me you'll end up chasing your tail. The car would run light years better on any map from factory up with the factory intake. It really can never be perfect again once changed. Which sucks. But that is the way it is.
 

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Yes. I ran the exact same intake. You could rescale the maf but take it from me you'll end up chasing your tail. The car would run light years better on any map from factory up with the factory intake. It really can never be perfect again once changed. Which sucks. But that is the way it is.
Just curious what issues you ran into from trying to rescale? I've never dealt w/ it on this platform, but on my WRX I had done it and while it's a huge PITA to record all of the data points, overall it was pretty straight forward and resulted in very good trims. Surprised that this platform would be much different.
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