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Creeping afr and timing issue

G

gambler87

New member
This is my setup
04 Comp G
3.4 pulley
Lq4 maf
Airaid 4" intake
Aem dry flow filter
42# injectors
Sd headers
Yt 1.84 rr

I'm tuning it using dhp

I have zeroed out my PE afr vs time table, thinking that my injectors should increase pulse width to keep my desired PE afr which is set at 11.5.

In second gear I floor it in tapshift mode and my afr goes down to 12.0 then as the rpms climbs it maxes out at 13.3. My timing is locked in at 9° ( which I know I need to add timing). I have 0 kr issues.

I have scanned and tuned using table modifier 7 times tuning the maf table.

What I'm wondering is why are my injectors not making up for the added air from the blower thus keeping my desired afr?
 


Your timing should be no lower than 15*. You need to adjust your afr via the maf hz table when you go wot. You are asking to kill your car at that 13.3. What are you fuel trims at?

I havent used dhp but same principles
 
Yeah that is what I have been tuning using the table modifier. U just put ur scan data in and ur old maf airflow table and then u set some parameters and it spits out a new maf table using the scan data. I've done that to get my fuel trims where they are now. I just thought the ECU would tell the computer to dump more fuel since they aren't staying at the desired afr that I've selected.
 
No. That would be if you setup a table to see the commanded to actual afr difference. I would just manually just look at your afr gauge and see what its at at what rpm and adjust accordly until its on, slowly adding like 2 % fuel in the areas needed.

Edit: with your mods i think you will only be able to get like 15* timing out of it unfortunatly or pulley up to a 3.5
 


Basicly if you look at your scan logs when you go wot you will see what hz you are at. Typically around 7k. Then you just add fuel above that manually untill you are at you desired afr 11.5:1 would probly be best for you.
 


id put your pe stuff back in there before you blow it up.

when using eddies to tune your maf are you using the last new file that was created by eddies as the current maf file with the next new scan?


and you have to make damn sure your trims have fully learned before you scan and make more changes with eddies.


that pe file actually makes a noticeable difference if you tune it. i got my hands on a zzp tune for my year car, loaded the zzp canned tune pe settings and it ran lean and had kr, so ive made my own version thats like 1/2 way between stock and the zzp #'s and so far its been a lot of work changing all them damn numbers. re did it 4 times already getting it dialed in. this version feels damn good so far.

if you'd like to try the zzp pe settings let me know. ill email it to you. or the last one i set up last night. still waiting for the trims to learn but so far its looking good for my car any way. the more you play the more you figure it out.

check your base a/f ratio too. its in the pe folder too.

i was using the maf kpa #'s to tune my injectors to get my trims in order too. that worked like a charm before the pe tuning, then i put the stock file back in to see if it made a difference or not. so far its looking to be rich at idle for sure. but not the -12 it was before hand at idle and light gas.

if my trims lock up a 0.0 wot and i have any kr ill maf tune it with eddies to kill that off. if the trims are whacked out at idle ill turn tune them again with the maf kpa again.

ive got another tuner guild like jerrys tuner note book, it goes into more detail. if you like i can email that to ya too. helps you to under stand stuff a bit better.
 


I already had that tuner guide but I reread it and I think I'm going to start over on this tune.

If I have a lq4 maf and a 42# injectors. Do I just upload stock data for both things and then tune the injectors to get ltfts down first and then tune in maf table?
 
thats what id do. set up the 42's if not done right yet, ( i have no idea how to do it, but jerry goes over it in his tuner book) and the stock maf file for that lq4 maf.

let the trims learn, then you can adjust the injectors flow rate if need be, then maf tune it some.

your ltft's will be all over the place while they learn.
 
Yeah I tuned in my 3.6 pulley to damn near perfect. But to go down to my 3.4 pulley I had to switch injectors.

I will start over and see if it gets me and better results.

Have u ever heard of taking a percentage of ur commanded afr and actual and them adding or subtracting them to the Hertz maf file?
 
you dont need 42's to run a 3.4 pulley. i had one on my car. stock l67 injectors, ran fine. i even tuned 4* of kr out of that pulley.
 
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