Local LNF issue

[04redline]

A local member who got her car flashed was having issue with the tune on her vehicle. She complained that the car's boost would raise to 22, as its supposed to, then fluctuate and drop down to 14-16 psi, and either it would rebuild again, or it wouldn't. It seems to be very sporadic, and it doesn't seem to happen to often. The funny thing i noticed, 2 out of the 3 throttle % pids are sitting at 100%, though her Throttle pedal itself is only reading 50% IF that in some cases. And im positive the car got pushed to 100%. So far now, its looking like a bad throttle body.
I have also been told that, if the lnf vehicles aren't tuned by using the write entire feature it can, at times, make the car react funny, or make some sensors act up much like what is going on now. Is there any truth in this?
Anyways, Here is a small log were i was finally able to watch the issue happening first hand. Any advice is always welcome. I appreciate all feedback
Thank you!

[shabby]

I have also been told that, if the lnf vehicles aren't tuned by using the write entire feature it can, at times, make the car react funny, or make some sensors act up much like what is going on now. Is there any truth in this?

Not true, just do a write calibration only, an entire write isn't needed.

As for the throttle issues, it seems like the pedal is only being pushed halfway, yet the ecm is fully opening the throttle body which does happen sometimes as i've experienced the same thing, just one of the quirks a torque based system i guess.
I suggest you do some pulls yourself and plant the the pedal to the floor and log it, and then if you notice the pedal position is still showing 50% then its probably something with the pedal sensor.

[Russ K]

You need to find out why the car isn't entering PE at WOT, before melting the pistons!

Russ Kemp

[04redline]

Not true, just do a write calibration only, an entire write isn't needed.

As for the throttle issues, it seems like the pedal is only being pushed halfway, yet the ecm is fully opening the throttle body which does happen sometimes as i've experienced the same thing, just one of the quirks a torque based system i guess.
I suggest you do some pulls yourself and plant the the pedal to the floor and log it, and then if you notice the pedal position is still showing 50% then its probably something with the pedal sensor.

Excellent thank you very much. Just curious, how did you manage to fix your issue?

[shabby]

Don't think its an issues, its just how it works.

[Terminator2]

A local member who got her car flashed was having issue with the tune on her vehicle. She complained that the car's boost would raise to 22, as its supposed to, then fluctuate and drop down to 14-16 psi, and either it would rebuild again, or it wouldn't. It seems to be very sporadic, and it doesn't seem to happen to often. The funny thing i noticed, 2 out of the 3 throttle % pids are sitting at 100%, though her Throttle pedal itself is only reading 50% IF that in some cases. And im positive the car got pushed to 100%. So far now, its looking like a bad throttle body.
I have also been told that, if the lnf vehicles aren't tuned by using the write entire feature it can, at times, make the car react funny, or make some sensors act up much like what is going on now. Is there any truth in this?
Anyways, Here is a small log were i was finally able to watch the issue happening first hand. Any advice is always welcome. I appreciate all feedback
Thank you!

Wow is all I can say. It is definately an issue with the car itself. The boost climbs to 21 psi then falls really badly to 14.5 it is knocking like mad and I believe based on the log the the throttle is opening only 45-50%. It is doing that with the stock tune as well so it is definately some mechanical issue.

[justmike]

Check all the hose clamps! As a matter of fact replace them with T-Bolt clamps if you can.

[04redline]

Wow is all I can say. It is definately an issue with the car itself. The boost climbs to 21 psi then falls really badly to 14.5 it is knocking like mad and I believe based on the log the the throttle is opening only 45-50%. It is doing that with the stock tune as well so it is definately some mechanical issue.

Yes sir, It was doing this on the stock ecm as well. I was way ahead of you of having her put in her stocker for testing. Fortunately, the dealership was able to replicate the issue. So its gm's issue now.
Thanks guys for the help!

[cobaltssoverbooster]

if this is rissa's car i would reccommend checking the throttle position sensor in the pedal itself and also having a peek at the valves with a borescope after checking for boost leaks.

i would go to the pedal first since it seem to not want to enter p.e. than maybe the pedal is messed and its not showing up. pedal could also be sporadic. the others are a more consistent error. i hope you not letting her pull the shit out of that with it knocking that hard those pistons wont take much more of it.

[04redline]

That was on someone elses tune, since then shes gone back to a gm tune and taken it back to gm, to get it checked out. They gave her back her car today. This weekend, were going to log some more and she if its continuing to do so.
Lol@ the knock comment. Though my post count may be small, im not that much of a rookie. Thanks for the advice though, we'll look into it.

[cobaltssoverbooster]

yea shee was going to come down and we were gonna check that out and tune it but i had a engine malfunction of my own and decided to reduild my lnf head to full race so i couldnt help.. thanks for helpin her out man ive been meaning to.

[04redline]

Not a problem sir, The issue has officially been resolved. There was a fault in the ecm. Swapped to her stock one, threw my tune on there, shes a happy camper again. 100% tps and all. When i pull the logs from the lappy, ill post them as verification.
Interesting on the Race build. I may have to pick your brain about a few things on the lnf tuning im still unfamiliar with. Ill throw ya a pm a bit later.
-Shaun

EDIT for pics

http://i134.photobucket.com/albums/q...Untitled-2.jpg

[cobaltssoverbooster]

yea man hit it up sometime im in the anaheim area so u ever wanna stop by or something thats cool just let me know. as far as the mod i had a timing error problem with the timing chain and i was set back so i would have it done cept for that. bad instructions boo helm.

[04redline]

yea man hit it up sometime im in the anaheim area so u ever wanna stop by or something thats cool just let me know. as far as the mod i had a timing error problem with the timing chain and i was set back so i would have it done cept for that. bad instructions boo helm.

Oh right on man, im in the San Bernardino area. Sucks about the timing thing. Least you didn't go my route and destroy a sleeve, lol. Ill be in touch with ya soon.

[Terminator2]

Not a problem sir, The issue has officially been resolved. There was a fault in the ecm. Swapped to her stock one, threw my tune on there, shes a happy camper again. 100% tps and all. When i pull the logs from the lappy, ill post them as verification.
Interesting on the Race build. I may have to pick your brain about a few things on the lnf tuning im still unfamiliar with. Ill throw ya a pm a bit later.
-Shaun

EDIT for pics

http://i134.photobucket.com/albums/q...Untitled-2.jpg

I told her the problem was her ECM. Before she even brought it to the dealer.

[04redline]

I told her the problem was her ECM. Before she even brought it to the dealer.

Sure ya did sir.

Hahaha, j/k

[Terminator2]

Sure ya did sir.

Hahaha, j/k

When she told me that it was running fine with the stock ECM I knew the other ECM was the culprit. Computers are stupid sometimes LOL.