High LTFT on Ktuner basemap 19.5/23

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Anyone experience really high LTFT on the Ktuner starter basemap 19.5/23? I'm stock aside from the PRL street CAI and running 91, but saw a constant -17 or higher LTFT when driving like a grandma. I flashed back to factory but I'm just wondering what other people did to lower the LTFT or if theres some way for me to diagnose the problem. I already checked out 27won's afr page but I'm still somewhat new to the whole tuning thing and learning. Any feedback is appreciated!
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You'll need to post a datalog for starters. A constant -17 is EXTREMELY rich and is way off for a base tune on a near stock setup. You didn't touch the MAF scaling at all, right? And you double checked the PRL intake install?
 

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There are no changes in the MAF scaling when you compare the KTuner basemap and the factory map. It should not impact you LTFT at all. -17 is a bit high, anything more than 10% either direction starts to be concerning for LTFT. I would look over your intake install and make sure everything in installed securely.
 
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You'll need to post a datalog for starters. A constant -17 is EXTREMELY rich and is way off for a base tune on a near stock setup. You didn't touch the MAF scaling at all, right? And you double checked the PRL intake install?
I don't have a datalog but I'm kind of nervous to load up the basemap tune again to be honest, I'm on factory currently averaging -7 for now. I haven't touched the Maf scaling either.
 
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There are no changes in the MAF scaling when you compare the KTuner basemap and the factory map. It should not impact you LTFT at all. -17 is a bit high, anything more than 10% either direction starts to be concerning for LTFT. I would look over your intake install and make sure everything in installed securely.
I'll be sure to look over the intake again for anything noticeable tomorrow!
 


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I reinstalled the PRL cai and checked all the clamps to make sure they were tight. I also went ahead and cleaned the MAF sensor and cleaned out my filter even though it barely had 4.5k miles. My STFT is hovering around -8 to -15 idle and my LTFT when I'm driving averages around 0 to -7 depending on traffic. (All on the factory tune) I'm not quite sure how normal this is since I'm getting mixed answers from other people in terms of what STFT I should be seeing idle if anybody can point me in the right direction (I put a datalog of what I saw driving partial highway mostly local city street). I was planning to stay on the factory tune a couple of days to see how things play out though before I hop back onto Ktuner's basemap.
 

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Your LTFT sounds decent now. What period of time is it swinging that much though? If you just reset your ECU, I guess that makes sense that it will be a bit more varying until it settles in. I can go weeks on end and it barely changes. Mine pretty much always stays within a few points, but then I'm not doing much driving in traffic which could affect things.
 
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Your LTFT sounds decent now. What period of time is it swinging that much though? If you just reset your ECU, I guess that makes sense that it will be a bit more varying until it settles in. I can go weeks on end and it barely changes. Mine pretty much always stays within a few points, but then I'm not doing much driving in traffic which could affect things.
I drove for 40 minutes or so yesterday and in total maybe 80 miles while on factory since I flashed from the basemap. I'm just worried about the rough stft idle now. I'm thinking about swapping to the stock intake to find out if its my intake causing the negative trims or something else. If I sit idle for 15 minutes or so my LTFT hits -10 and I'm not keen on seeing how high it could go.
 


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I don't monitor my STFTs much as they do swing pretty wildly. If I recall correctly at idle w/ the engine load changing as the alternator and A/C compressors kicking on and off, the STFT can be a bit all over the place. Cruising along at light throttle and w/o making any sudden throttle changes, then the STFT should stay steady right around 0.
 
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I don't monitor my STFTs much as they do swing pretty wildly. If I recall correctly at idle w/ the engine load changing as the alternator and A/C compressors kicking on and off, the STFT can be a bit all over the place. Cruising along at light throttle and w/o making any sudden throttle changes, then the STFT should stay steady right around 0.
Yeah that was the impression I had but I saw in other threads that an stft at idle should ideally be 0 unless my injectors are at fault.
 

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Yeah that was the impression I had but I saw in other threads that an stft at idle should ideally be 0 unless my injectors are at fault.
Yes, it should be, as long as the A/C and alternator aren't kicking on and off, which changes the engine load.
 

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What I'd like to see is you temporarily going back to the stock intake and re-flashing the KTuner basemap. Then run and post a datalog of 20-30 minutes of mixed driving.​
I know that's a bunch of work for you but I'd like to look at your trims on that log. IMO, there is virtually no way the tune is the culprit to your -17 LTFT. Those tunes were designed and optimized on a stock 1.5 turbo.​
This might be one of those process of elimination things.​
 
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What I'd like to see is you temporarily going back to the stock intake and re-flashing the KTuner basemap. Then run and post a datalog of 20-30 minutes of mixed driving.​
I know that's a bunch of work for you but I'd like to look at your trims on that log. IMO, there is virtually no way the tune is the culprit to your -17 LTFT. Those tunes were designed and optimized on a a stock 1.5 turbo.​
This might be one of those process of elimination things.​
I totally agree with that, I plan to change to the stock intake today and I'll post up a log tonight.
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