LTFT on stock car

Hondanickx

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Did anybody ever monitored the LTFT on a stock car ? (1.5t) I've been using the Torque pro app a few weeks now and my LTFT and STFT are always negative . LTFT is -10 on cold start and fully warmed up -8 -7.Is that normal for a stock car to take out fuell all the time ? Air/fuel values are spot on 14.7 on idle and 11 -10.8 when WOT .Max boost i see is 15 Psi peak.
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When was the last time you replaced the engine air filter? My LTFT was around -8 when I replaced mine and LTFT went back to zero
 

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Did anybody ever monitored the LTFT on a stock car ? (1.5t) I've been using the Torque pro app a few weeks now and my LTFT and STFT are always negative . LTFT is -10 on cold start and fully warmed up -8 -7.Is that normal for a stock car to take out fuell all the time ? Air/fuel values are spot on 14.7 on idle and 11 -10.8 when WOT .Max boost i see is 15 Psi peak.
It's adding fuel, stock is rich.
 
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Hondanickx

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It's adding fuel, stock is rich.
Afaik it's taking Fuel away cause it's rich yes.
"A negative fuel trim percentage indicates a taking away of fuel while a positive percentage indicates an adding of fuel."
 
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Hondanickx

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When was the last time you replaced the engine air filter? My LTFT was around -8 when I replaced mine and LTFT went back to zero
It still has the first air filter ,only have 22000km .Could be the air filter needs replacing.
 


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Afaik it's taking Fuel away cause it's rich yes.
"A negative fuel trim percentage indicates a taking away of fuel while a positive percentage indicates an adding of fuel."
This is correct.

Unrelated to my above statement, please keep in mind that the fuel trim logic is not the same on European vs North American ECUs. Couldn't tell you why, it would be nice if Honda just left everything the same. :)

That being said, there is nothing alarming about an LTFT of negative 8-10 percent. The ECU is doing it's job, no worries there.
 

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Afaik it's taking Fuel away cause it's rich yes.
"A negative fuel trim percentage indicates a taking away of fuel while a positive percentage indicates an adding of fuel."
yeah sorry i meant stock map (adding alot of fuel) as it is rich & you are right ecu is taking fuel away.
NA,EU & SAM are different as for my case there is no LTFT for Asian Market (maybe not all but for malaysia, indonesia & singapore probably thailand too have no LTFT) ECU's just STFT.
surprisingly your WOT is not too rich over here WOT goes to 9.5-10 AFR on stock.
 
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Hondanickx

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I'll try with a different air filter and see if the trims go down closer to zero.;)
 

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My trims are always between -7 and -3, sometimes go to -10. Consider replacing (or at least check) the stock filter before 20k km if there is too much dust/polution where you live. Im using a washable K&N filter, because the stock filter was getting clogged and stealing turbo spool speed down low and mid.
 

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I'll try with a different air filter and see if the trims go down closer to zero.;)
SRI or CAI should bring those stock trims to about half of what you're seeing now without tune.
get reputable ones, there are some known to do more harm than good.
 


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Hondanickx

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My trims are always between -7 and -3, sometimes go to -10. Consider replacing (or at least check) the stock filter before 20k km if there is too much dust/polution where you live. Im using a washable K&N filter, because the stock filter was getting clogged and stealing turbo spool speed down low and mid.
I used the prl stage 1 for a while (before i was using the torque app) that did run a little better from what my butt dyno felt.
The stock filter has about 16000-17000km and it looked a little dirty but not too much.I ordered the new Sprint filter panel filter for the 1.5t .Will test that one when it arrives here.
 

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If it's not clogged I don't think it's going to make much of a difference. Keep us posted :)
 

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My trims are always between -7 and -3, sometimes go to -10. Consider replacing (or at least check) the stock filter before 20k km if there is too much dust/polution where you live. Im using a washable K&N filter, because the stock filter was getting clogged and stealing turbo spool speed down low and mid.

I confirm, all the European ECUs controlled by me have similar values
 

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With the stock intake I get STFT / LTFT down to -5. With the PRL SRI, it gets to -10 occasionally, usually its -6 or -7. That is in traffic or moderate traffic. When cruising STFT/LTFT are almost 0 with the PRL and dead 0 with the stock intake. The AEM was horrible for the V at least, -14 for STFT, LTFT consequently fell to -11. I took it off after a couple of days. Waste of money
 

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it is possible that on crv the ecu works in closed loop
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