Is Software/Firmware update my problem?

[robof16]

I'm sure it's going to be embarrassing when I find out what I'm doing wrong...

BLUF: I'm getting what looks to be a dangerously lean condition with the "correct" injector data, exactly as if I set B4001 significantly higher than spec.

Background:
- 6.0L with mild cam. Just an injector change, preparing for some boost. Cylinder volume and fuel pressure spot on, confirmed with 2 different gauges. WRT, cylinder volume, engine is bored .020 over, so that’s why it’s higher than stock.
- New 12613412 (50lb) GM Injectors with good data supplied by Selman Performance. Also tried another set of used (same model) injectors with same results.
- Still logging Calc-VET with V7.5 Scan Tool and AEM 30-0300.

Observations:
- VE table values from the logs are much lower than expected - Lower than with previous injectors, (GM/AC Delco 8.1L) and lower than a stock LQ4.
- I experimented with the IFR set to 42 lb/hr and the Lambda/AFR lined up, followed commanded, etc., and the truck ran great. Even in this case the VE values looked about 10-15% lower than with previous injectors.
- With “correct” injector flow rate, LTFT’s are zero for the log. With the lower (wrong) IFR, they look normal, about what you would expect.

I don't tune very often but the only thing that is different is the latest software/firmware update, which (I wish I hadn't done) requires V8 to flash the PCM.

Log titled “50” is with the correct IFR set and “42” is the test with 42 lb/hr set.
Tune file has incorrect (42 lb) IFR but otherwise correct injector data. VE table is the starting point from the previous injectors, not altered by data from latest logs.

[robof16]

Interesting, I tried the 42 lb IFR just because I suspected I was sent the wrong injectors. As it turns out, the truck performs really well with that setting.
Also, a possible clue is; CALC_VET produces VE table values that are significantly lower (by 20+%) than expected with either IFR entered. By expected, I mean compared to the VE table generated with the previous/original injectors which was really close to the stock LQ4 table (mild cam).
In other words, the VE table errors are about the same as the IFR error, if that makes sense.

From JoeCar's tuning notes:


Wideband reports the same EQR as commanded EQR if these are all true:
- B3601 is the correct stoichiometric AFR for the fuel being used,
- B4001 IFR and injector characterization tables are correct,
- when/if PCM uses VE: B0101 VE is correct,
- when/if PCM uses MAF: B5001 MAF is correct.

With the wrong IFR set, the WBO2 correctly follows the PCM EQR commands. With the correct IFR set, they do not agree.

[robof16]

To close this out...
This was strange and frustrating. I'm still not positive exactly what the problem(s) were but, between changing software and updating to COS all is well now. Truck runs great and everything is working as it should, with the correct IFR set in the tune. The software change came about from a support ticket with EFILive. I updated both V7.5 and V8 via links they provided to resolve compatibility issues between the two - I still modify tunes quite a bit with V7.5.

[nonnieselman]

To close this out...
This was strange and frustrating. I'm still not positive exactly what the problem(s) were but, between changing software and updating to COS all is well now. Truck runs great and everything is working as it should, with the correct IFR set in the tune. The software change came about from a support ticket with EFILive. I updated both V7.5 and V8 via links they provided to resolve compatibility issues between the two - I still modify tunes quite a bit with V7.5.

Glad to see you figured it out.
Ive used a ton of those injectors with the data i sent and never had a issue.