Blown-Interceptor

I am tuning my STFTs.

I have MAF Fail Freq=0, LTFT=off, PE Enable=640.

Whenever I bring the rpms up around 4000, the car craps out, and gives my the Reduced Engine Power.

Here are the codes:

P1514 - Airflow to TP Sensor Correlation High

P0103- Mass Air Flow (MAF) Sensor Circuit High Frequency


Any ideas??? I am at such a loss. Should I give up trying to tune my STFTs?

Thanks,
Jason

BLOWNZO6

How/Why are you tuning for STFT? You should be tuning the LTFT.

You have to adjust the table for the 1514 error.

Go into engine diagnostics
There is a table there for 1514 error.

If you are going to run 7 psi.. take 14.7+8 / 14.7 = 1.54
Multiply the whole table by 1.54

Should get rid of your error.

You also have to set your mass fail frequency higher.. I set mine at 15000 Hz

I assume you have a wideband as well...

Blown-Interceptor

I have been tuning for LTFT, I thought I also had to tune for STFT as well???

Should I Disable the 1514 code?

I do not have forced induction...what table are you talking about?

The stock MAF fail frequency was 11250, will it be ok to raise it that high?

No wide band yet...I am just trying to get the LTFT and STFT in line. I was under the impression that I had to get the LTFT and STFT in line first before I went to dyno???

Thanks,
Jason

BLOWNZO6

Sorry I assumed you were tuning for forced induction.. yes you can raise it over whatever level is giving you the error, start lower if you want.

Just try raising your 1514 table a bit then, say mulitply the whole table by 1.1 and see if it stops giving you an error.

Not sure how you are tuning STFT and LTFT separately? You should only be tuning for LTFT, it is a function of STFT.

Yes you want to get your LTFT in line before doing WOT tuning you are correct.. I was referring to the wideband, which is necessary for correctly doing speed density tuning, the ONLY reason for disabling the MAF sensor.

Nick

Blown-Interceptor

Where is the 1514 table? I have a stock MAF, I was told by Ed Wright to never mess with the MAF if it is stock. I am not really sure I trust him after all the BS I went through with him.

As far as tuning for LTFT. I am using this tuning document over on LS1tech, here it is:

http://www.ls1tech.com/forums/showthread.php?t=304025

I look foward to your feedback on that tuning doc. Maybe I have been going about this all wrong?

Thanks ALot for the help!

Jason

Dixit

Well honestly you need to leave that MAF Fail at 11250, no point in raising it to 15000. I mean all stock 98 C5s have 11250. Its because of the MAF design. Might as well leave it that. You wont be hitting that range on an NA car anyways. No point in raising it to 15000.

Tuning via STFTs is quicker and more efficient than tuning via LTFTs. Yes the LTFTs is a function of STFTs. But if you disable LTFT through the VCM and tune via STFTs you will get it done quicker and in my opinion more accurately. Once you got the STFTs where you want them (like you were looking at the LTFTs) then you just enable LTFT back on and you will be spot on.

Dixit

Bink

jason - Are you trying to tune your VE with a Speed Density (SD) setup (mafless)? The tuning doc on LS1Tech is basically an SD tuning doc.
If you're trying to drop into SD then you probably need to set your MAF Fail limit to "0". What tuning tool are you using??

Dellz06

Are you maxing out your MAP at 4000rpm?

Without a 2-bar MAP, you can't tune SD above 105 kPa.

EDIT: I see you don't have a s/c listed -- my bad. If you set the MAF freq to zero, you need to disable the 3 MAF codes (like 101, 102, 103 -- can't remember exactly). Set them the #2 option and disable the SES light for each.

John.

Dixit

All you need to do is set the MAF fail freq to 0, dont need to disable any codes. The only code you will get is the P0103 code, no need to disable it as it will come on only during SD mode and kinda shows you are in SD mode. If that bothers you, then you can disable the SES light for that code only.

You wont get P0101 or P0102.

Dixit