Running extremely rich in boost/breaking up

[mgnta217]

I have a twin turbo 4.8l. Runs great at idle and cruising. AFR at idle is 14.7-15.0. Cruising its at 13-14. When I go into boost, AFR drops to 9.5 and feels like the engine is missing. I have tried leaning out the boost ve table but it leans out my idle to 16 and cruise AFR to 15-16 and still cuts out. Anyone have an idea what to look for next?

[joecar]

Post tune file and some log files.

[mgnta217]

2201222013

[mgnta217]

I just got the wideband hooked up to the flashscan so I'll make more log files

[joecar]

A0001 and A0002 are out-of-range (see the blue dog-ears)...

there's a trick to setting them in-range:
set them to 99%, save file, exit tunetool, open tunetool, set them to 100%, save file.

[joecar]

not related to your question:

B3616, B3615: 75% and 90% are too restrictive... set it to 65% below 3200 rpm, and to 35% above 3200 rpm.

B3618: set this to EQR 1.2354 below 4400 rpm also.

B3647: those stoich cells will cause OL-STFT trimming, set them to EQR 0.99 (like you have in the last 2 columns).


Do you have catalysts...?
Do you have EVAP system...?
Do you have Secondary AIR system...?

[joecar]

Remove these pids:
O2S11
O2S21

Add these pids:
HO2S11
HO2S21
RPM
KR
DYNAIR
DYNCYLAIR
EQIVRATIO

Make sure a MAF DTC shows up immediately.

[mgnta217]

no cats, no egr, no evap, no secondary AIR. No MAF, speed density running 2 bar

[joecar]

In the tune need to disable cats, evap, secondary air.

[joecar]

Which MAP sensor do you have...?

[mgnta217]

AC Delco 213-1631 2 bar

[mgnta217]

updated tune and more log files, one in town and one wot throttle220202202122022

[joecar]

I'll take a look...

[ProperTuningOG]

Your A0009 is very very rich. Is this a referenced regulator and raises with boost? What injectors are you running? Ditch using B3618 for enrichment and use B3647 so you can command proper out of boost numbers and ramp to boost.

You are leaning out the main fueling because the MAF is not failing correctly. When the MAF isnt failed right everything will run lean. Some of the OSs do not like the DTC value on non emissions. Switch it to A:1 trip. Also, I would suspect the maf is gone completely?

[mgnta217]

Completely mafless, running 42 lb injectors

[ProperTuningOG]

42 what? How is the regulator and rail setup? This will define the shape of the A0009 table.

[joecar]

I think Team208 is saying to do something like this:
- B3647: ramp this up to something like EQR 1.22 in the last column;
- B3613: set this to 105 kPa;
- B3618: set this to boost fueling (EQR 1.235 is maybe ok, EQR 1.26 is safer during tuning);

Team208, any refinement on those value...?

[mgnta217]

Delphi 12613412 injectors. Stock rail and regulator

[mgnta217]

I’ll take a look at those tables when I get off work and try to do a few more test runs if it quits raining. I really appreciate the help by the way. This is the first boosted application I’ve attempted to tune.

[joecar]

Do you have a manifold-referenced FPR (what Team208 is asking) above...?

Measure rail pressure with FPR reference disconnected (remember to reconnect after measuring).

42 lb/hr injectors rated at what pressure (and what brand are they)...?

[joecar]

Team208 is saying that you want to see a MAF DTC

( without this, the PCM tries to calculate what MAF should be, and it's always wrong ).

Get this sorted out first.

[joecar]

Also, on your next log, remove pid HO2S12, and add HO2S21.

[ProperTuningOG]

The injectors you listed are flex fuel 50 lb at 4 bar.......

[mgnta217]

They are GM Delphi injectors, Static Flow Rate at 43.5 PSI: 440cc/min, 42lbs/hr. I

[mgnta217]

Yes 50 lb at 4 bar

[joecar]

22027

[ProperTuningOG]

50 at 4 and you are saying you are running stock pressure....... Tune shows 42s on a return style system with stock regulator.

[ProperTuningOG]

There is too many BASE TUNE SETTINGS not setup properly to even begin to chase something wrong. The tune is fat, the injectors data is wrong. Have to have the right base to build off of, if not, you will be chasing your own tail the entire process.

[joecar]

Measure rail pressure with FPR reference disconnected (it should be 58 psi, i.e. 4 bar);

42 * sqrt(4/3) = 48.5 lb/hr (close enough to 50 lb/hr) = 6.11 g/s

[joecar]

He would be better to start with a stock tune, and add in only the edits required.

[mgnta217]

I didn’t even think about the pressure difference when I changed the injectors data. I’ll get back behind the computer and start reviewing everything again.

[ProperTuningOG]

He would be better to start with a stock tune, and add in only the edits required.

Exactly. Back to the minimal changes to get things going. Then when everything is known, tune whats needed.

[mgnta217]

I started with a stock tune and converted it to cos3. Should I start again fresh and retry it?

[ProperTuningOG]

What we are saying is list out all the specs in one place. Injectors, map, fuel system, how its setup.... We'd be happy to help but everything needs to be organized together and a proper base flash needs to be built. Right now its a train wreck.

[mgnta217]

Ok I’ll start with a basic cos3 build off my stock tune and get everything organized. I really do appreciate the help and I’ll repost once I’d get everything in order. Thanks again

[joecar]

summary:

- find stock tune with same OS;
- do COS update from stock tune;
- fix out-of-range tables/cells (remember exit/reopen trick);

- set injector tables (IFR and the other tables) from data provided (using measured rail base pressure);
- set MAP scaler/offset to match 2-bar MAP sensor;
- set MAF to fail properly (see a MAF DTC show up);

- set B3647 to ramp up non-boost fueling (and avoid stoich cells);
- set B3618, B3613 to provide boost fueling;
- reduce B5913 and B5914 spark advance to accommodate boost (what is the spark vs boost rule-of-thumb);

- disable systems not physically present;

what else...?

visually inspect everything, make sure everything is connected/bolted properly, and no leaks.

[joecar]

+1 on what Team208 said, being organized is important to tuning properly.

[mgnta217]

ill start all of this later today, thanks again

[mgnta217]

when setting the ifr, should i set it flat (referenced) or sloped (non-reference)?

[ProperTuningOG]

Is the rail returnless? I feel like questions keep getting asked with no answers.

[mgnta217]

fuel system is a stock return type fuel system. static frp with no reference is 56 psi. injectors are 50lb/hr @ 58 psi. I am currently trying to find injector data sheets for rest of the injector data.

[ProperTuningOG]

Can you put up the stock COS before modding? When you flash the COS, then flash the stock file, then read... I want that read. I'll help setup

[joecar]

when setting the ifr, should i set it flat (referenced) or sloped (non-reference)?


fuel system is a stock return type fuel system. static frp with no reference is 56 psi. ...

keeping track of details:
referenced FPR.
56 psi base pressure mreasued.

[mgnta217]

2001 Chevy Silverado
Stock 4.8l engine
Twin 60mm turbos running 5-8lbs boost
Return type fuel system with stock rails and regulator (delphi 12613412 injectors 50lb/hr @ 4BAR)
Reference FRP @ 56psi
Completely MAFless
EGR Delete
EVAP delete
Catalyst delete
2 BAR MAP sensor
TH400 transmission

Stock COS
22042

[ProperTuningOG]

Whats the MAP part number?

[mgnta217]

AC Delco 213-1631 2 bar

[ProperTuningOG]

is this drive by wire?

[mgnta217]

Yes

[ProperTuningOG]

This is by no means tuned but is a start for a boosted app. I have setup the flex fuel injectors based off a gen 4 ecm. They are set for 4 bar. A few percent low on pressure is not going to hurt, if its all stock parts its normal to have it +- a few psi. YOU WILL HAVE TO LOG AND TUNE THE VE!!!!!! Timing is set safe, 14-15 degrees cool boost and pulls more as temp goes up. If you have a question or are unsure on a setting, ask.

22044

[mgnta217]

I compared yours to the one I have been working on today and I'm glad to see I was on the right track with my injectors, after your help of course. I'm gonna tweak and flash this tune and make some logs

[ProperTuningOG]

Theres a lot more done in that than just injector scaling.

[mgnta217]

I

[joecar]

IThe forum somehow truncated your reply... we've been seeing a lot of this recently...