Problems with STFT tuning???
Best way to put into SD mode, is by Changing the Fail Freq to 0, and then put it back to the orginal value when you done with SD mode.
Dixit
I did what you said, I tried it again. It happened again, brought the rpms up a little and there it is reduced engine power and car runs like ****. I think I might forget about STFT tuning. I am at a loss, I have no idea what do to.
Any ideas???
Here are the codes:
P1514 - Airflow to TP Sensor Correlation High
P0103- Mass Air Flow (MAF) Sensor Circuit High Frequency
Go to the P1514 table and increase it by 25% across the board. And then try it again, that may solve it. Some of the s/c'ed vettes actually double that table. I increased mine 25% and it was fine, never went into reduced power mode again.
Dont give up, you almost there. This is the end of your problems and then onto tuning.

Dixit
Go to the P1514 table and increase it by 25% across the board. And then try it again, that may solve it. Some of the s/c'ed vettes actually double that table. I increased mine 25% and it was fine, never went into reduced power mode again.
Dont give up, you almost there. This is the end of your problems and then onto tuning.

Dixit
Where is the P1514 table?
I wish I had a Blower on my Vette...that would be a wet dream.
Thanks for the help!
Jason
There in that tab at the bottom is a P1514 button.
Increase that table by 25% by multiplying all values by 1.25. That should clear your issue and let you run in SD mode.
Believe me you are almost there. I had all the same problems.
Dixit
There in that tab at the bottom is a P1514 button.
Increase that table by 25% by multiplying all values by 1.25. That should clear your issue and let you run in SD mode.
Believe me you are almost there. I had all the same problems.
Dixit
Thanks alot for your help! I will check it out when I get home from work.
I also posted on the corvetteforum about my problem. One guy said not to tun STFT, just tune for LTFT. When I multiply by 25%, do I mess with the MAF Fail Freq? Or leave it at 0?
You can check it out if you like...
http://forums.corvetteforum.com/show...80&forum_id=91
I hope this works...thanks Again!
Jason
LTFTs take normally 100miles to fully learn and even then its not fully learned because if you didnt hit that cell once and hit it at say at mile 101 and only hit it for a split second, the LTFT on that cell is not learned. Because if you look at that same cell on the STFT and its not +/- 3, then its not learned completely. If your STFT cell showed 5 or even 10, then its still learning to adjust the LTFT. Thats why tuning via STFTs with the LTFTs disabled is quicker and in my opinion more accurate. Once you turn the LTFTs back on, it will be within -5 and +5. Then just calibrate the maf to keep it in that range.
Multiple the entire 1514 table by 1.25. Dont mess with the MAF Fail freq. Leave that at 0 so you can do your SD tuning. Once you are tune completely with tuning then move that MAF fail freq number back in that (just put your original number since thats whats been working for you) and enjoy your new driving experience.
Dixit
The Best V8 Stories One Small Block at Time
You should reset your fuel trims each time you flash the VCM with changes to the VE table so you can recheck the Fuel Trims to check how close you are.
Dixit
You should reset your fuel trims each time you flash the VCM with changes to the VE table so you can recheck the Fuel Trims to check how close you are.
Dixit
LTFTs take normally 100miles to fully learn and even then its not fully learned because if you didnt hit that cell once and hit it at say at mile 101 and only hit it for a split second, the LTFT on that cell is not learned. Because if you look at that same cell on the STFT and its not +/- 3, then its not learned completely. If your STFT cell showed 5 or even 10, then its still learning to adjust the LTFT. Thats why tuning via STFTs with the LTFTs disabled is quicker and in my opinion more accurate. Once you turn the LTFTs back on, it will be within -5 and +5. Then just calibrate the maf to keep it in that range.
Multiple the entire 1514 table by 1.25. Dont mess with the MAF Fail freq. Leave that at 0 so you can do your SD tuning. Once you are tune completely with tuning then move that MAF fail freq number back in that (just put your original number since thats whats been working for you) and enjoy your new driving experience.
Dixit
Tried it today...it worked GREAT! Thanks for the advice!
When you say reset the fuel trims...how do I do that? I have not been going that whenever I reflash the pcm.I hope I don't have to start all over again?
Well shouldnt be too bad in that you did reset, just do it now and log again and see where you are at.
Dixit
But dont hurt to reset it anyways.
Dixit
Thanks!
The log I took yesterday. There were quite a few 0 and 1. A few 3 and 4 postiive and negative, but nothing way out of wack.
This is what I took today.
Last edited by Blown Interceptor; Aug 10, 2005 at 08:44 PM.
Dixit





