Cobb AP Discussion Thread

[Rawyzf]

long term fuel trim

Thanks bova80. And that is similar to AF Ratio?

 

[Qwik6]

I dont know exactly but I think its the percentage of fuel it adds or subtracts.

 

[Rawyzf]

I dont know exactly but I think its the percentage of fuel it adds or subtracts.

Ok, that helps me some

So is there a target range? I see you had 0.0 - 0.7 or something like that, then another guy had it in the 6.0 - 9.0 range or...can't remember!

 

[bova80]

no its not similiar to afr....well i guess kind of

fuel trims basically tell the ecu hwo much fuel to add or subract to keep the AFR's stoich. + LTFT pull fuel and - LTFT add fuel. STFT (Short term) is what the car is doing at the moment and the basically become the long term trims after a while. when your stft are aroudn 0% then your car is basically done learning.

 

[Qwik6]

Well. Running the Economy map and the stage 1+ 91 map my LTFT's were perfect. Meaning the highest I would see was +5 and the lowest -2. Idle at 0. On the other hand the stage 1+ 93 map I was about +7 at idle and +11 accellerating. Wierd thing is I am seeing a steady 3.8 KR on the 91 map and the 93 map I would see very little. Maybe a spike of 1.8. Im changing back to the 93 map to reset the fuel trims.

 

[Rawyzf]

Thanks guys....the help is appreciated.

Another question for you....I have an Injen CAI, so I can't run the Stage 1 + SF correct? I need to get the Cobb SRI in order to do so?

 

[bova80]

yeah i wouldn't recommend running the stage 1+sf map if you hvae the injen. i mean you could try it and see how your fuel trims look thats the only thing you risk. i just remember a few saying they were way off but who knows, doesn't hurt to try.

 

[djdanny5000]

any input on my datalog???

 

[bova80]

yeah it looks damn near perfect. no problems that i can see. instead of equivalent ratio i always log actual afr. i dont know if there is a difference between the 2 just what i log.

 

[bova80]

i put it in a graph for ya.

 

[djdanny5000]

i put it in a graph for ya.

Thanks for the input and how do you put it in a graph?

 

[bova80]

just grab the data and insert into graph. i would search creating a graph in excel on google or something

 

[Qwik6]

Thanks guys....the help is appreciated.

Another question for you....I have an Injen CAI, so I can't run the Stage 1 + SF correct? I need to get the Cobb SRI in order to do so?

You can try the Stage 1+ FUCAI.

 

[Rawyzf]

You can try the Stage 1+ FUCAI.

Yeah, but I'd like to run a map that is on thier site, to be safe. Unless that one is on thier site and I missed it.

 

[bova80]

mzdspd.com its on my site and i get all the maps there directly from christian @ cobb. so the maps on my site are just as good if not newer than the ones on their site.

 

[Rawyzf]

mzdspd.com its on my site and i get all the maps there directly from christian @ cobb. so the maps on my site are just as good if not newer than the ones on their site.

Excellent!

 

[Qwik6]

Bova. Can the 900 rpm be applied to any map?

 

[coyfish]

what map you running qwik?

 

[Qwik6]

Stage 1 +SF 91 as of now. Changing back to 93.

 

[bova80]

the 900rpm idle will be once the tuning software is out. also i believe you will be able to turn off certain check engine lights, like perhaps the ones for the vtcs, egr, or also being catless.