PE Fuel Multiplier
02-25-2007, 03:00 PM
#1
On The Tree
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PE Fuel Multiplier I have a question, what is wrong with using the PE multiplier tabe to aid in tuning WOT. I have previously tuned my car a few months ago with the exception of WOT. Rather than having to completely retune the car VE, spark, MAF I decided to drop the PE table slightly to obtain the results I was looking for 12.24 to 12.8 AFR this seemed to work great. I did this with the maf enabled, LTFT enabled, etc etc, just like I drive the car on the street. I have checked my maf, LTFT's are neg and my WB all look to be right were they should be. But from my previous tune the commanded AFR was high 11's, I never changed the tables because it was tuned via LTFT's. Now I have a commanded of 12.4 and an actual of 12.8~9. Any insight on this would be appreciated
02-25-2007, 04:58 PM
#2
Is there something wrong with it? no, not necessarily, people have been doing it forever...but you'll find by dialing in your other sensors to reflect accurate data gives you a more accurate tune within nearly the same amount of time. Looking at a pe table that looks like the rocky mountains isnt what I like to see in a tune, but if it works it works.
02-26-2007, 05:38 PM
#4
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This is a case of two wrongs DO make a right.
Either your VE table or your MAF table, or both, is lying to the PCM. In order to get the result that you want, you now have your PE table lying to the PCM.
You got the result that you wanted, and only you know that it took a bunch of lies to get there.
I'd never do it that way, but that's just me. I tune both the VE and MAF tables so that I get exactly what I put in the PE table.
Take a look at your VE table. Does it look like this one?
Either your VE table or your MAF table, or both, is lying to the PCM. In order to get the result that you want, you now have your PE table lying to the PCM.
You got the result that you wanted, and only you know that it took a bunch of lies to get there.
I'd never do it that way, but that's just me. I tune both the VE and MAF tables so that I get exactly what I put in the PE table.
Take a look at your VE table. Does it look like this one?
02-26-2007, 05:42 PM
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I would never tune by PE alone, a accurate VE/MAF tune is better to have especially because then it allows you change WOT AFR accurately and very quickly.
02-26-2007, 08:34 PM
#7
There is no "right/wrong" way to look at the PE multiplier.
It is the multiplier that sets your "Commanded air fuel ratio" You set this to what you want your airfuel to be, and adjust airflow to get the actual = commanded.
If you tuned the old way, raping the PE table, to get an actual airfuel ratio to not equal the actual, your not tuning the pcm properly.
Ryan
It is the multiplier that sets your "Commanded air fuel ratio" You set this to what you want your airfuel to be, and adjust airflow to get the actual = commanded.
If you tuned the old way, raping the PE table, to get an actual airfuel ratio to not equal the actual, your not tuning the pcm properly.
Ryan
