Thread: Comp g tuning question

A table doesnt make then higher or lower, you clearly have a issue that is making the trims higher than normal.

I would just shut the car off while you wait anyway.

Heat soaking, higher IAT's, and coolant temp will just retard timing and likely that leads to seeing more knock.

Vacuum leak, incorrect injector info, a non tuned MAF sensor.


And + LTFT mean lean, a negative number means rich. So if the numbers are going above +10 LTFT you have a issue when it being lean and wanting to add fuel on it's own.

whos tune you running? sounds like your injectors need adjusting.

not really.

scan your mafs kpa, and ltft. along with what ever else you like to scan for.

make yourself a paper work sheet # it 10 20 30 all the way to 100. then write down the ltft for each cell in the maf kpa

say at 30 kpa, you see -8 ltft you would subtract 8 from the injector flow rate file. its set up 10 - 100 just like the maf kpa.

the guide ive read how to do this says to take the ltft number and add or sub tract as needed, but ive found if you take the full # you'll over shoot. so if it was 8 id take 5 out. and so on for each cell.

if you want i have a manual that explains this much better im sure lol i can email it to you if you like.


like five finger said, with dhp - #'s are rich, + #'s are lean.

so if you have pos trims, your adding fuel, neg you subtract.

take a little more than 1/2 the #, seems to have done the trick for me.

you can always put the maf scan in eddies and let that work the maf for you.

no thats for when you enter pe mode as per throttle %.

pull some timing at the top of wot.

you can add fuel in the injectors with the maf kpa like i explained before.

make damn sure your narrow band upstream oxygen sensor does not have more than 75,000 miles on it an o2 sensor gets to be unreliable over 50,000 miles as it is often skewed off of true stoichiometric.

leave the spark tables alone in bad fuel. they are like a safety net.


run 93 if you have it.

if you have kr try lowering the timing at the rpms your seeing kr.

well if you cant make it go away with the injectors take a degree or two of timing out.