motocooney

iTrader: (6)

So I have been trying to figure out why I can't get my car too run richer.

VIII stock turbo
FIC 850CC injectors/perrin rail
header/02 housing/turboback
intake
big FMIC
cams...all that stuff

I've been having terrible part throttle knock and some WOT knock.
I can't get the A/Fs any lower.

Here's my fuel map



And scaling and latency for FIC 850cc



the injectors are new this week along with a new Walbro. I was using PTE 780cc.
The new pump and injectors made no difference.

What could be the problem?

I get counts of 1-3 during a clean WOT. But when I'm just driving aroupnd going through the gears and stuff, I'll get 10-15 sometimes. It's always when I'm about half throttle. The A/F stays around 14-15 and I get knock. WTF? Please help. I'm scared to even drive this thing.

[CODETPS RPM timing IDC A/F knock load
42.745 2531.25 24 7.1 16.2 0 90.625
49.8039 2562.5 23 7.65 16.5 0 95.31
54.5098 2593.75 20 7.77 16.5 0 98.125
59.6078 2625 21 8.4 15.9 0 100.9375
65.098 2656.25 20 10.2 15.4 0 104.375
69.411 2687.5 19 10.32 15.4 0 106.5625
74.11 2718.75 18 11.02 13.4 0 109.375
80.392 2750 18 11.17 13.4 0 113.4375
84.7058 2781.25 18 12 12.7 0 115.625
92.1568 2812.5 17 12.13 12.5 2 118.75
98.039 2843.75 15 12.88 12.5 2 123.125
100 2906.25 14 13.64 12.4 2 125.9375
100 2937.5 13 14.413 12.4 2 129.6875
100 2968.75 13 13.44 12.2 2 133.125
100 3000 12 14.22 12.2 1 137.1875
100 3062.5 12 15.0266 12.8 1 143.125
100 3093.75 11 15.84 13.1 1 147.1875
100 3156.25 10 16.8333 13.1 1 151.875
100 3187.5 9 18.54 12.9 1 159.6875
100 3250 9 20.10666 12.9 1 165.625
100 3281.25 8 21.906 12.7 1 174.375
100 3343.75 8 23.76 12.3 1 183.125
100 3406.25 7 25.4333 12.3 1 194.6875
100 3468.75 5 28.12 12.3 0 208.4375
100 3531.25 5 31.16 12.3 0 220.9375
100 3593.75 3 34.8 11.8 2 239.0625
100 3625 2 37.76 11.8 2 257.1875
100 3718.75 1 40.8 11.8 2 274.0625
100 3781.25 2 43.106 11.5 2 280.3125
100 3906.25 2 43.333 11.5 2 264.375
100 3937.5 2 42.333 11.5 2 256.875
100 4062.5 3 43.333 11.5 2 255
100 4093.75 3 44 11.6 1 254.6875
100 4187.5 3 44.4266 11.8 1 254.6875
100 4281.25 3 44.7533 11.8 1 256.25
100 4375 3 46.06 11.9 1 255.625
100 4437.5 3 46.7133 11.9 1 255
100 4531.25 3 47.693 11.7 1 251.5625
100 4593.75 3 48.346 11.7 1 256.5625
100 4687.5 3 49.3 11.8 1 254.375
100 4781.25 3 49.28 11.6 1 254.0625
100 4843.75 4 50.96 11.6 0 254.0625
100 4937.5 4 50.56 11.6 0 253.125
100 5031.25 4 51.52 11.6 0 257.8125
100 5093.75 4 52.48 11.4 0 258.125
100 5156.25 4 53.12 11.5 0 260
100 5250 4 54.08 11.5 0 264.0625
100 5312.5 3 54.72 11.5 0 264.375
100 5406.25 3 55.36 11.5 0 265.3125
100 5468.75 3 56.32 11.5 0 264.375
100 5531.25 3 57.28 11.5 0 264.0625
100 5625 3 57.92 11.7 0 263.125
100 5718.75 4 57.34 11.4 0 262.1875
100 5750 5 58.28 11.4 0 260.625
100 5843.75 5 58.9066 11.4 0 257.8125
100 5937.5 5 59.533 11.4 0 257.1875
100 6000 5 59.1866 11.3 0 254.375
100 6031.25 5 60.7866 11.3 0 254.375
100 6156.25 6 60.72 11.6 0 252.1875
100 6187.5 6 61.0266 11.5 0 250.3125
100 6281.25 6 61.64 11.5 0 249.6875
100 6343.75 6 62.253 11.4 0 248.125
100 6406.25 7 63.173 11.4 0 246.25
100 6468.75 7 62.1 11.2 0 245.625
100 6531.25 7 63 11.3 0 243.75
100 6562.5 7 63.6 11.3 0 243.125
100 6656.25 7 63.9 11.3 0 241.25
100 6687.5 7 64.5 11.3 0 319.6875
100 6812.5 8 63.946 11.2 0 238.125
99.6078 6843.75 8 64.24 11.2 0 237.8125
][/CODE]

Raptord

iTrader: (10)

Logs would help.

motocooney

iTrader: (6)

Log posted of a 3rd gear WOT

11.2 by redline. fuel map calling for ~8

Raptord

iTrader: (10)

Could be in an easier format to read, but whatever.

11.2 at redline is right where you want to be, your fueling looks fine to me. Just because the map says 8 doesn't mean the car is supposed to run that. the value in the map is just that; the value in the map. As long as your real AFR is where it should be (12.x at spoolup, 11.5 ish at peak torque and around 11.1 at redline), you're fine.

EDIT: A rescale on the load-axis might not be a bad idea either.

TouringBubble

iTrader: (2)

Verify that you don't have an exhaust leak. What are your fuel trims?

raasfaas

iTrader: (30)

This could be your injector scalings...did you check your low and mid fuel trims after swapping to the 850's? You won't get a true 1:1 ratio, but properly scaled should get you relatively close (depending on lean spool)

Boosted Tuning

iTrader: (12)

This^ first. Did you make sure you have no exhaust leaks and what are you low and mid LTFT?

And this ^. The number in the fuel map is just an arbitrary number. It doesnt matter that your fuel map AFR isnt close to your actually AFR.

And definitely +1 on the load rescale.

motocooney

iTrader: (6)

Low and Mid trims are -5 and -4. I don't want to raise the scaling any higher so I know that I need to decrease the latency a bit to get closer to zero but they're not maxed out or anything.

Sorry about the format on the log...I'll figure it out

I realize that the A/F is fine in the log but it's not fine during part throttle stuff. It's staying lean way too long before richening up. And it's knocking because of it. Everything's sweet when I'm flooring it but other than that, it knocks everytime I give any sort of half throttle. It sucks.

As far as exhaust leaks, anything that would matter (turbo header area) is easy to see or hear. And there is nothing.

Could MAF scaling have anything to do with it. I bought the car with a tune already on it with the intake and I haven't touched the scaling for that.

What do you think?

Thanks

motocooney

iTrader: (6)

Also, I realize that the #s in my Fuel Map will never likely be the same as actual A/Fs but I just don't like the fact that I'm so close to the minimum A/F value in my map and I'm hitting mid 11s ya know?

Before new injectors, I was running way more timing and making a ton more power without knock. Now I'm knocking with low timing and can't get any more fuel out of it. What's the deal?

thanks

riceclown

iTrader: (3)

just so you know my pte 880s have a scaling of 790.

I think there is a thread on here with all kinds of injectors and their scaling

raasfaas

iTrader: (30)

https://www.evolutionm.net/forums/ec...upermerge.html

motocooney

iTrader: (6)

I tried the scaling (770) and latency values from that thread for FIC 850s and it was WAY off for me.

The fact that my trims are close-ish means the scaling is in the ballpark wouldn't you think?

chamelieon

iTrader: (21)

my FIC880s were scaled to 750 and never had any lean issues

motocooney

iTrader: (6)

I brought the scaling down to 770 and used the same latency I was using when they were scaled to 812 and so far my idle trim is +.78 after about a half an hour of idling.

I'd say that's a bit better right.

Am I right that the lower your scaling the more fuel that the injectors are putting out? I know it's not as simple as that but that's the basic idea right?

Maybe the fact thathy were scaled to 812 (so close to their rated output) that I was kind of stuck with the fuel map tuning?

I'm beginning to think that something may be mechanically wrong, front o2 or something. Because everytime I've flashed the ecu lately (a lot) The car will go full lean and stumble when I first start it. Also at this time there is 0 STFT and the V of the sensor doesn't move very much. then if I slightly blip the throttle evrything goes back to normal.

It's still changing fuel trims so I know it's not totally dead.

Do these sound like symptoms of a bad front o2?

thanks

motocooney

iTrader: (6)

Bump. Anymore ideas on why I'm so close to bottoming out my target fuel map and only hitting 11 a/fs?

Or why my trims seems pretty close but my idle is ****ty now?
I don;t think this should be expected with 850cc injectors right? They're not that big.

What are the symptoms on these cars with a bad front o2 sensor?

Thanks.