50 trim @ 20 psi logs, WEIRD! need help diagnosing

[blcknspo0ln]

I did a log tonight and it confuses the crap out of me. my 50 trim was creeping to about 24 psi @ 6000 rpms.. but i was still running rich? wtf!?

if it helps, i think i have a boost leak in the TB somewhere.. I can't find the damn source yet though.

1k 2k 2.6k 3k 3.6k 4k 4.6k 5k 5.6k 6k 6.6k 7k
LO:
-8 -20 -20 -20 -20 -20 -20 -20 -20 -20 -20 -20
HI:
-31 -31 -31 -32 -32 -33 -39 -41 -41 -42 -42 -42

MBC at 19 psi creeping to 24 psi - 58* @ 87% humidity

RPM o2 Volt. Timing *
3500 0.91 13
3636 0.93 11
3796 0.93 9
3980 0.95 7
4168 0.95 5
4324 0.95 6
4536 0.93 8
4740 0.95 7
4940 0.95 9
5132 0.95 9
5296 0.95 6
5484 0.95 7
5672 0.95 9
5880 0.95 10
6008 0.93 7
6356 0.96 6
6376 0.93 7
6868 0.93 8

RPM o2 Volt. Timing *
4728 0.91 14
4908 0.93 9
5096 0.93 9
5324 0.93 7
5500 0.93 8
5660 0.93 7
5952 0.93 6
6044 0.93 6

 

[TimG]

I hate to tell you this, but you are running lean and most likely knocking. I have to let you in on a secret, your stock 02 sensor lies more then your best friend who is secretly railing your wife. Never listen to it. Get a wideband, then we will talk.

 

[blcknspo0ln]

good analogy.. haha, and yes, I know the narrowband is very off.. but i figured it'd still be around the right ballpark. oh top of that, nate @ dsmotorsport tuned my safc2 to those settings, I just wanted to see what the logs looked like..

he told me I was getting AFR to 10.8 at ~6000 rpms. guess not

 

[hellotbone]

Timing looks terrible seems your lean and knocking as Tim said. Richen it up a 5% across the top and give it a run and post it.

 

[Violater101]

He's definately knocking, not just a little, but ALOT. If your running an AFC, then you should atleast be seeing 18* of timing. You need to get a handle on the boost creep and fix the boost leak as well if its really noticeable before you start to tune the car. 24lbs of boost and pumpgas is not a good mix, especially when you don't have a wideband.

 

[CanadianTSi]

I would bring everything past -33 down to -33 and start from there.

 

[pneumo]

I would bring everything past -33 down to -33 and start from there.

You mean change those hi settings from-39% -41% -41% -42% -42%-42% so they're all -33%, right? That's what I'd do.

I'd also recomend you lower the boost while you're getting the fuel settings figured out. You might not be able to run 21 psi with your mods yet, regardless of the fuel settings. Tune it in steps.

A boost leak might account for the hi settings getting leaner as the rpm goes up, and for excess knock.

 

[Knuckles2.0]

why are the high settings leaner than the low? i dont get it...

 

[pneumo]

why are the high settings leaner than the low? i dont get it...

...because he has a boost leak. Either that, or the settings are all messed up, but since he said he had it tuned by a shop I'll vote for 'boost leak'.

 

[94Jettameowpsst]

-42%?!? Im lucky if i have 8 counts or less at 20 psi on my evo 3 with it leaned out 28-30. I mean i know the evo 3 blows hotter air given the small compressor housing but geez. Yea your definitely on the lean side. Id personally start at -20 or so pending on where your timing is leaned out even that much.

 

[blcknspo0ln]

-20 is waaaaaay too low.. my car runs pig rich at that setting..

anyway, I just lowered the SAFC2 and i'm gonna go get the info now.. be back in a little, oh yea.. did a boost leak test and found 2 huge ones. one at the TPS and one HUGE leak at my LICP [stupid ass meineke weld]

 

[blcknspo0ln]

1k 2k 2.6k 3k 3.6k 4k 4.6k 5k 5.6k 6k 6.6k 7k
LO:
-3 -20 -20 -20 -20 -20 -20 -20 -20 -20 -20 -20
HI:
-31 -31 -31 -31 -31 -32 -34 -34 -34 -34 -34 -35
2 boost leaks found, 1 at LICP, 1 at TPS [shaft seal]
56* at 90% humidity
MBC @ 20 psi creeping to 23-24 psi
RPM o2 Volt. Timing *
3644 0.93 15
3824 0.95 12
4012 0.95 11
4196 0.97 11
4380 0.95 12
4612 0.97 12
4836 0.97 13
5016 0.97 13
5216 0.97 14
5436 0.97 12
5636 0.97 11
5824 0.97 11

4548 0.93 15
4708 0.95 15
4916 0.95 13
5124 0.95 13
5332 0.95 13
5556 0.95 11
5712 0.95 12
5916 0.95 13
6084 0.95 14
6292 0.95 14
6440 0.95 14

eh, at least it's a better timing curve. boost leaks will be fixed soon and a new log soon
can't give up just yet

 

[prophecy7115]

Do you feel the difference?

 

[blcknspo0ln]

nope

 

[hellotbone]

Turn the boost down or get some better fuel.

 

[spyderturbo007]

why are the high settings leaner than the low? i dont get it...

This is based on the ECU's target AFR. At cruise/idle the ECU's job is to use the O2 sensor voltage feedback to shoot for an AFR of 14.7:1. This is the stoichometric point and the point of lowest environmentally harmful emissions.

At WOT the ECU shoots for 9.5:1 AFR (much richer than 14.7:1). Most people like to run an AFR of around 11.3:1 so you need to remove fuel to adjust the target AFR from 9.5:1 to 11.3:1, thus the leaner SAFC-II settings.

 

[PSIcho]

I was in the same boat about a couple of weeks ago... That boost leak is a BIG factor, once you fixed it you'll definately feel the difference and everything else, timing and fuel trims, will fall into place. Or at least it'll be much easier to tune.

 

[blcknspo0ln]

Turn the boost down or get some better fuel.

you saw my fuel mods, no?... rewired 190/ 660's

and I believe i read another thread that was involving tuning at high boost vs. low boost, and the conclusion was that tuning at higher boost because of the "hi airflow tuning" produced better timing / less knock..

yesterday i went to fix what i thought was the major boost leak and it felt all the same..lperhaps the ass-o-meter needs to be adjusted

 

[hellotbone]

you saw my fuel mods, no?... rewired 190/ 660's

and I believe i read another thread that was involving tuning at high boost vs. low boost, and the conclusion was that tuning at higher boost because of the "hi airflow tuning" produced better timing / less knock..

yesterday i went to fix what i thought was the major boost leak and it felt all the same..lperhaps the ass-o-meter needs to be adjusted

Yeah I saw your fuel mods. Turn the boost down to 18psi ish and give it a run and log it.

 

[Knuckles2.0]

This is based on the ECU's target AFR. At cruise/idle the ECU's job is to use the O2 sensor voltage feedback to shoot for an AFR of 14.7:1. This is the stoichometric point and the point of lowest environmentally harmful emissions.

At WOT the ECU shoots for 9.5:1 AFR (much richer than 14.7:1). Most people like to run an AFR of around 11.3:1 so you need to remove fuel to adjust the target AFR from 9.5:1 to 11.3:1, thus the leaner SAFC-II settings.

oh well thats makes good sense, is it the same for a 1g?

 

[spyderturbo007]

oh well thats makes good sense, is it the same for a 1g?

Um, yes and maybe.

Closed loop and open loop operate the same way, but I don't know what the target AFR for the 1g is at WOT.

Sorry

 

[pneumo]

Yes, the target A/F ratio for a 1G at WOT is also around 9.5:1.