What is the meaning of PRVR TP low thershold in Z32 ECU RB25

[louiswun]

As title.
Thx !

[Matt]

When you get a fuel cut, this is the recovery (RVR) point based on TP value (this may actually be injection pulsewidth value looking at my other specs here since it mentions 1/16ms as pulsewidth but would need to check it out further)

[RomChip200]

Matt, are you sure !?

PRVR has nothing to do with fuel cut feature.

As stated in the workshop manual, PRVR is a help to start the engine when the fuel temp is above 75°C (Z32).
Basically, when intake pressure > atmospheric pressure, a small tank with an unidirectional valve stores some positive pressure.( aka boost).
If fuel temp is very high on next startup (if fuel temp sensor is weak, the engine temp is used instead), the ECU exercises the PRVR solenoid to release this pressure to the FPR, meaning you inject additional fuel to counteract the initial fuel/engine high temp.
The ECU does so if rpm <2800 and TP <56. There's also a counter to shut the solenoid after a while.

Code: Select all

DATA:FFC2 prvr_rpm_low:       fcb 56                        ; ...
DATA:FFC3 prvr_tp_low:        fcb 56 

DATA:FF76 prvr_temp_low:      fcb 125                       ; ...
DATA:FF77 prvr_temp_high:     fcb 125                       ; ...
DATA:FF78 prvr_count_low:     fcb 30                        ; ...
DATA:FF79 prvr_count_high:    fcb 30         

RAM2:148B prvr_counter:       rmb 1