Turbo 5.7 WOT throttle issue

[akalshaikh]

Hi,

So am helping a friend dialing in his 2015 charger R/T. Has a single turbo (VS racing 7875), rods and pistons.

Mainly two issues, Misfire & WOT throttle keeps closing for some reason (am not lifting). Tried several things to remedy it with no use. (Tq mgmt and etc)

You can find the data log and the tune file here.

Please shed some light if he's missing something here.

We're running it around 10.8 AFR with 8 degrees of timing to be at the safe side. once we can figure out the throttle issue will start using meth injection and up the boost to 14 PSI

[LilSick]

Please shed some light if he's missing something here.

with the voltage reading fluctuating like it is

(in stereo with the throttle issue and the misfires)

i would not be surprised if it has a bad ground

a wiring issue or two

or a bad pcm

[akalshaikh]

The car was running perfect with the same cam.

Once we went the turbo setup. Didn't change anything else, we started facing this issue.

The only thing changed was added turbo and plugs and thats it.

Also, running LFR7 spark plugs gappd at 0.022"

[HaasExp]

Hi,

So am helping a friend dialing in his 2015 charger R/T. Has a single turbo (VS racing 7875), rods and pistons.

Mainly two issues, Misfire & WOT throttle keeps closing for some reason (am not lifting). Tried several things to remedy it with no use. (Tq mgmt and etc)

Have you and your friend tuned many boosted FCA vehicles on GPEC2 PCMs?

First thing that really stands out is the barometric pressure is still "learning" and updating when on boost. This totally messing up the pressure ratio parameter which is used to drive the fueling strategy among other things.
This needs to be disabled in the tune.

Also the sensed MAP switch is still disabled. This needs to be enabled when on boost.

These two things are considered the absolute basics to even begin tuning these on boost.

From a brief glance, the rest of the tune also looks quite concerning eg ANN turned off but the VE tables are not scaled for boost pressures etc.

[HaasExp]

with the voltage reading fluctuating like it is

Where are you seeing these voltage reading fluctuations?
From the longest log in only seeing a "battery voltage" fluctuation of between 13.6 - 14.20V. So a change of around 0.6V.
The "control module" voltage is even more stable than this (only 0.34V fluctuation). IMO I wouldn't be too concerned with the magnitude of these voltage fluctuations.

[akalshaikh]

Have you and your friend tuned many boosted FCA vehicles on GPEC2 PCMs?

First thing that really stands out is the barometric pressure is still "learning" and updating when on boost. This totally messing up the pressure ratio parameter which is used to drive the fueling strategy among other things.
This needs to be disabled in the tune.

Also the sensed MAP switch is still disabled. This needs to be enabled when on boost.

These two things are considered the absolute basics to even begin tuning these on boost.

From a brief glance, the rest of the tune also looks quite concerning eg ANN turned off but the VE tables are not scaled for boost pressures etc.

1- we've done several older gen. This is the first time we're doing 2014+.. this one is the learning car for us. It's out car

2- I'll try disabling baro learning and enabling sensed map.

3- as for the VE table, it was scaled for boot but i couldn't get the pressure ratio to read properly. No matter what I did, the PRatio was maxing out at 1.00 although it is scaled under airflow tab.

Thanks for your input,, highly appreciated

here are the DTCs also, P2110 !!

[veeefour]

VE is not tuned properly...you dont put 120% not going to use anything over 100%

Setting 120% for pressure ratio 1 is not going to increase the PR...

You need a good base to begin with this wont do...we can hook you with a base file(we build +100 turbo 5.7) but wont work for free.

[akalshaikh]

I am aware of that, VE should not exceed 100% but its working for me. bear in mind that these figures will drop will below 100 once we go for meth injection.

the fueling is on point and AFR is steady at 10.8 - 11.0.

Also, the VE table has been dialed in using the wideband to maintain 14-14.5 afr at part throttle which is what we are getting now. so for me, as long as the wideband is readying properly am good.

My only issue is that the throttle for some reason closes during WOT pull from 86% to 60% +/- and I am trying to figure out why its happening.

ETC Tq mgmt is disabled, and there is no relation between fueling or VE to ETC !!

[Stoopalini]

Neither your airflow nor your fueling are setup to handle boost or higher aircharge values. VE and PE tables need to be scaled, otherwise the PCM will hold those upper row values into the higher readings.

PRatio most likely wasn't reading correctly because you didn't have sensed MAP enabled. Calculated MAP will not read higher than Baro, it will hit a ceiling and stay there. The PCM needs to switch over to sensed MAP at some point ... 0.96 PRatio is a typical value for this.

Also check the Airflow limit in 39020 ...

[akalshaikh]

Update:

thanks for highlighting the issues with the file.

Currently on low boost i have 0 issues. When upping the boost, the throttle for some reason closes. you can see the log file attached. I didnt lift It just went into limp mode

I code came up P061A

I have doubts that it's torque model related

[LilSick]

i do not know where your mixture is but that thing has ran out of injector at your current boost level

add fuel pressure and lambda to scanner

[akalshaikh]

I am aware of that, we're injecting methanol before the throttle.

My afr is at 10.5,, my issue is why the throttle closes with P061A

[LilSick]

why are you reading AFR while injecting methanol???

the only way to data log pump gas and meth is to use lambda

[akalshaikh]

Yup, my wideband is reading.72-3 lambda with the water-meth injection

[jevan]

Did you manage to solve it? I also have the same problem on a 300c turbo 2006 5.7, error p061a

[veeefour]

We build and tune 5.7 turbos on daily basis and we have no issues. My base tunes are for sell if you guys want it.

[akalshaikh]

Solved the issue just now..

DM me so i text you my phone number text me on whatsapp I'll go through your tune with you.

No charges here. Lets see what we can do to fix your issue.

[akalshaikh]

Update:

Found the root cause of P061A
Found the root cause of throttle closing under WOT & vehicle hesitation during WOT.

All fixed.. time to give er' the beans.

[akalshaikh]

680 WHP
730 lb.ft of torque

11 psi boost with 13 degrees of timing.

Will up the boost once we upgrade the fuel system

[jefo]

Those are some good numbers! Still stock cam? Makes my pre-eagle setup look sad haha