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Discussion Starter #1
Hey guys I've been posting up over in the open/closed loop thread but I thought I'd start a new thread to keep that one focused on the CL issue.

I am getting random lean spikes (20-15 afr) during my runs and the CL comp is around 30% at times. Looking at my logs do things look normal. I have learning enabled but nothing is showing up in the learn table at all. All values stay at zero. When I first started with it I could see it adding or taking away fuel live in the table. It no longer does this. Not sure if that is a related problem or not.

Combo is a 393w with F1R Procharger. Car is about 3400lbs with a TH400 trans. Injectors are 80lb Siemens dekas. Wideband is the NTK sensor and I'm running cam2 fuel while at the track.

I tried to include most of the parameters so it may be hard to make out. Below is a link to the datalog file.

http://www.filedropper.com/hefilog20120606-202551

 

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Discussion Starter #2
Holley told me that it looks like RF noise. But they failed to explain what that is or how to fix it. I don't have the oxy sensor wiring routed near any ignition components.
 

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EFI/N2O JUNKIE
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How close is the tune for full throttle? At some point you should have the closed loop limits down to +-5%.

What are you using as an rpm input? That trace is pretty nasty-looking.

Did you peddle the car off the line? I am assuming the very top line is the TPS sensor.

I can see a small dip in the fuel pressure. If it is a boosted combo the fuel pressure should rise with intake pressure, one to one. Have you looked-into that?

Lean spikes in the wideband can be from several things. A common one is a misfire, can be from way too lean or way too rich. A bad plug wire on the side of the engine with the wideband can also look like that. I don't know about the RF noise thing, have not experienced that myself on a wideband. I know the Innovate LM-1 had a lot of spike-issues that looked just like that. They were electrical noise. Didn't matter since it wasn't being used for closed-loop feedback, in your case it does matter. That is why I set the correction limits to +-5%, even +-2% when the tune is done, so random noise doesn't effect the engine.
 

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Discussion Starter #6
Here is the global folder. You guys can see the fuel maps in there. Let me know if the these links dont work.

http://www.filedropper.com/393w2

Mike,

If I remember right I am using the ignition signal off my MSD Digital 6 box. The white wire from the TFI harness goes to the input signal to my box. I am running the Ford TFI ignition set up with a Mallory distributor. I have it wired up as the Figure 6 shows in the 8.4 Ford TFI section in the wiring diagrams.

I think the tune is close at WOT. Most of the time the CL comp hovers around +/- 5% or so. Since it won't learn I am having to go in manually edit the cells.

Yeah that TPS spike at the begining is probably my fault. I didn't pedal the car off the line. The car left really hard (at least for what I'm used to.) It only dropped to 87% at the lowest for just a spit second. It must have yanked my foot off the pedal or something. Usually I dont have a problem keeping it pegged. Sixty foot was around 1.36 on that pass. It mph around 139.

I'm not sure why there was that dip in the fuel pressure. It doesn't usually do that. I have the base set at 40psi and it does come up with boost to around 50psi. I'm only making about 12psi I think.

Thanks for the help guys.
 
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