N52 Not Revving Up

EMU PRO
1

Hello,

I have an N52B25 in a 325i racecar project with an EMU Pro 8 and a PMU 16 implemented.

This car received a fresh wiring loom, it starts and idles…DBW is calibrated but won’t rev up when the accelerator pedal is pressed/the throttle body opens. In contrast the RPM consistently drops about 200RPM. VANOS is currently not being actuated (so it’s in its relaxed position) and the Valvetronic is forced open to approximately 5mm valve lift (this shouldn’t really influence the engine’s ability to rev).

Unfortunately there is no lambda data yet as i have not been able to get the LSU4.9 working. I can say that when it bogs down it also smells rich, the injector pulse time also rises. We have constant fuel pressure so that isn’t the issue.

I have tried TPS strategy and MAF strategy, still waiting on a working MAP sensor so that hasn’t been attempted yet.

I have searched every corner and every setting of the EMU Pro software and cannot figure out why it does this…

Does anyone have any recommendations or tips?

I cannot upload a log file yet as I am a new user.

michal.kowalski 2

obraz

3
4

Thanks, please share your project as well.

5
6

There isn’t much data available to help diagnose the issue.

A few things I noticed:

  • Your injector calibration looks unusual. Please verify that it is correct.
  • The injection angle values also seem questionable, especially when using the “Start of Injection” control method.
  • We need more sensor data to help with troubleshooting. A WBO is essential. Without it, it’s difficult to determine whether the engine is running rich, lean, or if there is another underlying issue
7

Thanks, I will look into the injector calibration. What exactly looks unusual to you?

The issue with the WBO is that I cannot get it to work at all. I have quadruple checked the wiring with the LSU4.9 datasheet and everything is wired correctly:
Connector Pin 1 (IP) → B20
Connector Pin 2 (VGND) → B23
Connector Pin 3 (Heater -) → GND
Connector Pin 4 (Heater +) → B2
Connector Pin 5 (EMPTY)
Connector Pin 6 (VS) → B21

UA Voltage reads 1.497V

UR Voltage reads 4.928V

Heating the sensor through the changes nothing and nernst cell temp stays at 0°. No lambda reading is made either, it stays jumping 0.999-1.000…

8

The heater is connected to GND on both sides. Auxiliary outputs are low-side. You have to connect Heater + to 12 V and Heater - to some ECU output, B2 is fine. Take a look on the following example: