Swap N52b25 to N52b30

kamal251991 · 06-02-2026, 12:57 PM

I just swap n52b25 to n52b30
I’m using my b25 wiring all the same
Map maf sensor and injector used from b25 are the part number are same
When I crank the engine took long time to start and it stall a lots ,when try to accelerate like it going to stop
Anyone can help me ?

Brandoch · 06-02-2026, 02:52 PM

Quote:

Originally Posted by kamal251991

I just swap n52b25 to n52b30
I’m using my b25 wiring all the same
Map maf sensor and injector used from b25 are the part number are same
When I crank the engine took long time to start and it stall a lots ,when try to accelerate like it going to stop
Anyone can help me ?

Scan it.....

philpose1 · 06-02-2026, 09:11 PM

You’ll need to flash the DME with the correct N52B30 software.. even though the sensors and injectors are the same, the fuel/timing maps are different. Running B25 software on a B30 will cause the long crank and stalling. Get it coded to B30 spec and it should run right

06-02-2026, 12:57 PM	#1
kamal251991 Registered 0 Rep 1 Posts Drives: 523i F10 Join Date: May 2025 Location: Mauritius iTrader: (0)	Swap N52b25 to N52b30 I just swap n52b25 to n52b30 I’m using my b25 wiring all the same Map maf sensor and injector used from b25 are the part number are same When I crank the engine took long time to start and it stall a lots ,when try to accelerate like it going to stop Anyone can help me ?
	Appreciate 0 Tweet Quote

06-02-2026, 09:11 PM	#3
philpose1 Banned 77 Rep 87 Posts Drives: F44, F92 Join Date: Apr 2026 Location: Cleveland,Ohio iTrader: (0)	You’ll need to flash the DME with the correct N52B30 software.. even though the sensors and injectors are the same, the fuel/timing maps are different. Running B25 software on a B30 will cause the long crank and stalling. Get it coded to B30 spec and it should run right
	Appreciate 0 Quote