tribe

iTrader: (13)

Injectors are 680cc from Buschur.
Injector latency
4.68750 4.104
7.03125 2.424
9.37500 1.608
11.7188 1.152
14.0625 0.936
16.4062 0.744
18.6768 0.528

20psiMR

iTrader: (6)

That fuel map made me spit my starbucks all over the screen My boss actually came over and asked me what was wrong

I hope razor can help you out with that scaling, that has to be it. Thats ugliness

nj1266

iTrader: (6)

This file should help you scale your injectors. It is a good start. It was posted in the injector scaling thread.

tribe

iTrader: (13)

Thanks for the help. The logs don't make sense to me. The attached file shows how the air fuels are okay until just over 6k, where they go lean very quickly.

From EVOScan, MAP reads 328 (boost cut at 315, timer 1500). Is this log showing boost cut? If so, it makes no sense for the ECU to lean out the mixture and add timing.

Not shown on the graph, but AFRMAP stays close to 200, while CALCLOAD decreases quickly. What exactly is AFRMAP?

IPW decreases with airflow, which makes sense. This tells me it's not a fuel map or inj scaling/latency issue. Anybody experience an issue with the MAF reading low at high rpms???

l2r99gst

iTrader: (2)

That doesn't look like a misfire or fuel cut to me. The injectors aren't being shut off, so it's not fuel cut (boost cut). It look more like you have some air metering problem or something wrong with the MAF. Were you full throttle for the entire log in that screenshot?

FWIW, here is an old DSMLink log of mine showing a misfire that I had at about 5500 RPM when I was trying to run too much boost. Just to the right of the vertical line is where the misfire occurred. Tell tale signs are a downward spike in front O2 voltage or upward spikes up and down in the wideband reading.




Edit: I had to make the image less than 100K, so it is hard to see because of the lost detail, but the top blue line is front O2 voltage, and the PLX wideband is more clearly visible towards the middle/bottom in light blue.

Eric

tribe

iTrader: (13)

Yes, the chart shows WOT the entire time. Looking at the logs, the AFR goes from 12.3 to 16.2 in less than 0.5 seconds. No way when I'm driving can I react fast enough.

The more I look at the logs, the less it makes sense. I do think it must be a MAF issue. Thanks for your help.

l2r99gst

iTrader: (2)

The spikes in my graph are about .1s of data each. The three spikes that you see in my AFR are .3s worth of data.

I guess that I can't completely rule out a misfire in your case...perhaps with more data I would be able to tell for sure. But, I don't think you should try to log that anymore and cause more damage.

What physically happens when this occurs? What do you feel or hear?


Eric

tribe

iTrader: (13)

Feels like a slow rev limiter at 6k rpms. I thought it was misfire. But, looking at the logs, I'm convinced there's an issue with the MAF reading.

When I installed my PLX and routed my EGT sensor wire, I removed the plastic scoop that directs air near my buschur intake. I wonder if doing this causes too much turbulence at the MAF causing these issues? I need to put the air scoop back on and see if it helps.

gunzo

iTrader: (2)

tribe, what you experienced is actually detonation control by the ecu ..if you log the knock, you should see an increasing trend in knock as you lean out ..

When you have a misfire, your AFR actually goes rich for a while..

From the looks of your fuel map, either your injector size is wrong / your injector latency is wrong ... OR your fuel pump is still stock / dying ..

OR you just have a clogged fuel filter ..

If you have a fuel pressure gauge, a dropping pressure as rpm increases indicate an inadequate fuel pump.

tribe

iTrader: (13)

I don't have a fuel pressure gauge. I have a Walbro 255LPH installed. The MAF is reading low at high rpms, which I believe is the issue, not the fuel pump. If it was the fuel pump, then the IPW would stay high and I would see the lean condition.

A fuel pressure gauge is probably a good investment though!!

tribe

iTrader: (13)

Finally found the problem. I have the MAF signal connected to the R500. Somehow, there is some interference/crosstalk between the MAF signal and the R500. I disconnected the MAF signal from the R500, and now the car runs pig rich (10:1) at high rpms!! I'll post a graph later.

l2r99gst

iTrader: (2)

Glad you got it figured out. At least I was right with my original guess.

Eric

tribe

iTrader: (13)

Attached is a graph of 3rd gear WOT with the only difference being with and without the MAFs connected to the R500. Scary what a huge difference it makes!!!