Injector/fuel question

[asshanson]

I recently decided to get the BluMax 1350 injectors and got rid of my old 1600s. I recently checked my fuel trims and both the low and mid are both around 6%, so I need to change the global fuel compensation from -50 to -45 or so.

However, yesterday I was noticing that whenever I went full throttle (haven't done this in awhile) it would peg the wideband at 10:1 (probably richer) and misfire/sputter a lot since it was so rich.

These two things are conflicting, I was thinking my fuel trims would be -6%, but the opposite is true. It wants to be richer at idle/cruise, but its so rich it doesn't run right in open loop. Other than injectors I haven't changed anything on the car.

Ideas?

[Swifty1638]

you check your fuel pressure at the regulator?

-A. Swift

[turbotalon1g]

your wot enrichment too much? or did you do a pull with them pulled back?

Or do you have V3?

[asshanson]

No I have v2 still. I sort of expected the fuel trims to be that way because I downgraded from 1600s to 1350s, so it makes sense they were positive 6% (I also raised fuel pressure back to 43.5 base).

However, when I do the calculation for injector compensation:
1350/1.35 for e85 compensation = 1000cc injectors on pump
(450/1000) - 1 = -55%

I made sure the deadtime was on, the low and mid fuel trims are close to each other, but they dont go to zero until my global is -45%. This definitely explains why it's so rich at WOT (extra 10% fuel from what calculations suggest), but why is it so messed up at idle and cruise?

Should I let my low and mid fuel trims chill at +10% and be 11:1 at WOT? Or should I make the trims zero and have to mess with the fuel settings above 4k rpm?

[Shane@DBPerformance]

(450/1350)-1 = -66.6666666666666666666666666666666666666
-66 * .7 = ~ -46

So, I would just go for the -45 and then go into your airflow settings and lower the MAF settings starting at 400 or 800hz all the way up to 2400hz down 10%. You might have to play with the 400hz setting to see what works best for part throttle and boost onset.

[asshanson]

Ah, I thought the e85 compensation was done on the injectors before dividing by the stock size. I'll set global to -46% for a few days and check out the result (I accidently reset the ECU and fuel trims while installing my sub...)

I looked at my airflow table and everything except the first two sliders are at 10%. Just the lower small honeycomb is removed. I'll try setting those back to zero and see what the result is.

[Shane@DBPerformance]

You might not want to touch the lower airflow range(up to 250 or 400), if -45% was going to put your fuel trims at 0.

[asshanson]

Well -45% put my fuel trims within +/- 1% so that's all set. I checked my catch can and it was full, probably dumping blowby into my turbo and fmic, yay.

Anyway, I set my airflow sliders > 400hz back down to zero, and then did some logging. At almost full throttle and 25psi it said airflow was 2800hz at 6500 rpms, which is definitely more than it should be reading. It was richer than 10:1 still and sputtering like crazy. But it explains why it's dumping so much fuel in, I doubt it's actually flowing that much air.

What could cause this? I'm pretty sure there aren't boost leaks. There was quite a bit of oil right there from where the catch can line came into the top of the intake pipe, would that mess up the reading?