You raise many complicated issues. Will address as many as possible below:
First and most important: The PW reported in $8d and I believe all other GM masks is NOT the Final PW sent to the injectors. What's reported in the DDS is PW after o2 corrections if in CL, or calculated PW without o2-related corrections if in OL --- all before any other compensations (see below). This is why S_AUJP v6 was changed to report Final PW. Final PW reflects everything in the true PW sent to the ECM to fire the injectors:
Synchronous includes (Normal Injector firing 160 times a second):
- o2 adjusted PW if CL (Factory reported PW)
- PW for AE-MAP, if active, minus a coolant-based fuel limiting adjustment if:
- AE-TPS is Active, or
- 0x045 b6=’AE-TPS-Limit Fuel Out PW Calculation' is ON, or both are set
- Compensation for Low PW if applicable
- PW compensation for Voltage is always be added
Asynchronous includes (fired as needed 160 times a second -- none of this is in Factory reported PW):
- AE-TPS
- Deceleration Fuel Cut Off Stall Saver (DFCO-SS)
- A/C-just-on
- Once the AE-TPS PW component has been computed, if applicable, the following PW may be added:
- 3.90ms PW (0x5EC) is added if DFCO-SS is active
- 1.95ms PW (0x5A4) is added the first time the A/C clutch is engaged (A/C-just-on)
- PW compensation for Voltage is always be added
VE: VE from the tables is always adjusted for barometric pressure at prior key-off or current key-on, whichever is larger. That adjustment at sea level with Factory values from the Table at 0x81F is somewhere between no adjustment to Table value and +3.9%, so have to allow for that when looking at VE. BARO adjusted VE is that used for all fueling-related calculations.
AE: AE-TPS is instantaneous and gone, like a carburetor pump-shot. AE-MAP lasts a little longer, but after the initial PW effect, it's decayed-out fairly quickly so likely little effect on WOT PW/AFR
AFR: Look at the attached document to understand how AFR is calculated. Search for "Compute an AFR". Also, it's important to understand how temperature is used in the PW calculation. Look at the discussion at "How Flag 0x018 b4 Affects BPW". If the stock MAT sensor is not used and is relocated into the intake air stream, it's generally best to set 0x018 b4=0 so the coolant/MAT differential is not considered. Only MAT is used. But if the MAT sensor is in the plenum (factory set=up), you can use the b4=0 setting; but must recognize that the sensor is reporting heat-soaked temp and not the real Intake Air Temp.
Bottom line: PW varies significantly with temps!
HTH, Elky
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