Excessive Closed Loop Oscillation between 1%-9% TPS

[forevertrj]

The map I provided won't be perfect youll probably need to adjust it a bit. Street tuning isnt perfect either, if your getting little spikes of 1 or 3% richness that may not be what's going on as the data logging isn't perfect you really need 2 people in my experience, one person who has a steady foot to keep the Mani pressure perfect, and at the right rpm while you plug away.

[CGF20BOOSTED]

Yes, a driver would be ideal... a good driver. One would think it's easy to obtain a driver. This is done all by myself. I am getting close. I'll have to tinker with the dead times some more. There is a slight change in A/F when an electrical load is applied (like 14.7 to 14.0). So I am very close with the dead times. I don't mind having to re-tune the map after dead time alteration. Its practice and I strive for perfection. Its a bit of a learning curve but I know I can get this done. As of now, the part throttle is a "night and day" difference compared to my last tune. Now I can cruise without that annoying oscillation while in closed loop. After reading some of the posts on this forum, I realize that dead times are a common problem with tuning. I'll upload the Map when done. Anyways, thanks again for your help.

[forevertrj]

Yea it's really hard to find a driver luckily I've got a driver and he can stay exactly where I need him to while I dial in values, I'm going to try and build a dynamometer using an accelerometer and an adrino board by using all the hondata inputs for speed and rpm, and such should be fun, glad to hear about the dead times being improved, my cars deadtimes are dialed in properly and it still fluctuates a small bit, currently running different injectors then the ones I posted for you, those are the new ones I have yet to put in, and any time you need a hand let me know, it would be sweet to see if you modified the map since I changed it, and to see what changes needed to be made

[CGF20BOOSTED]

That's good to know that some variation my occur with the injector dead times. Must be a common issue with larger injectors? I'll post up the map when I'm, done. Probably won't till later on in the week. As of now, I can cruise without oscillation. Many thanks sir. You are a BAD ASS!

[CGF20BOOSTED]

I was talking with my co-worker about my tuning and injector dead times or lag times. So correct me if I'm incorrect. The lag times is the time it takes for the injector to open and start to spray fuel? If that's the case, I can scope the injector with voltage on one channel and amps on another channel. Then I can graph and see exactly how long it takes for the injector to open. Boom! Now I'll have the correct dead times for my injectors. No more guessing. Let me know what you think.

[forevertrj]

I just did a quick read over and it seems you're right dead times are like the "open sesame" time it takes to start squirting fuel so the ECU calculates this into your fuel tables so it can be opened at the right time, check this page out, ALSO important to note!!!! you'll need to be applying fuel pressure to this injector while testing, and it will need to be identical to the pressure you are running on your fuel rail, you can't just do it dry, as you can see from my previous injector dead time post picture, the injector isn't always 1000cc, it's only 1000cc at the given fuel rail pressure and it will have that dead time at that fuel pressure, as pressure goes down so does dead time, as fuel pressure goes up so does dead time.
http://www.hywell.org/plhelp/injdutycycle.html

[CGF20BOOSTED]

They will be tested while the engine is running. And we will test at each voltage interval. I'll let you know with the results

[CGF20BOOSTED]

So, in other words... injector reaction time. Why call it dead times? Who gives a f#@k when the injector is off or dead? I'm glad I have a lab scope.

[forevertrj]

Because the injectorn is dead, aka not spraying fuel until the dead time is over, or it isn't fully operational until the end of the dead time

[CGF20BOOSTED]

Lol. I hear ya. I don't care what its called. That's a debate. I just care about what it means and understanding it and knowing how to tune them in. We call them reaction time. Tomato tamato.

[CGF20BOOSTED]

I scoped the injector waveform today. They are high impedance (saturated) injectors. So the wave form looks like this;
So the "reaction time", "dead time", "lag time", I saw was .62ms @ 14v. Tomorrow I'll retry with my coworkers lab scope. I used mine today. I just want to confirm that both scopes get the same result. I have made another map with the scoped dead times but haven't tuned it yet. I will post the results later.

[forevertrj]

Sounds good, what brand injectors are you running again?

[CGF20BOOSTED]

RC

[forevertrj]

Did rc not have a data sheet for your injedtors.?

[CGF20BOOSTED]

Yes. I was unfamiliar at the time of install and tuning. Those injectors broke my tuning virginity. I am upgrading to 1650 FIC injectors soon per the full build on the F20b. I'm aiming for the end of summer. Now I should not have any issues with dead times. Hahaha :-D Thanks for your help again.