Siemens MS43 Retrofit MAP Sensor

Modern engines are almost exclusively equipped with pressure sensors to measure manifold absolute pressure (MAP).

The M5x engines don't have this sensor, that could be very handy when converting the engine to forced induction, or if you simply want to know MAP.

As of today, this sensor is for data logging purposes only, but will be used for additional features in the future. For those who still want to reftrofit a MAP sensor we write this article including a list of parts and tools you need.

Requirements

• Crimp tool
• 0.5mm² FLRy wire (preferably in three different colors)
• MQS Quadlock pin female for 0.5-0.75mm² wires(Tyco 963729-1)
• Bosch MAP sensor 20-300kPA (0261230119)
• Bosch Compact 1.1a connector housing female (1928403966)
• Bosch Compact series BDK2.8 pins (0.5-1.0mm² 1928498056-L)
• Seals for BDK 2.8 pins (1928300599)

A) additionally if you chose to solder inside the ECU

• Torx 15 screw driver to open MS43 case
• 0.25W 0-Ohm resistor or a short piece of insulated wire

B) additionally if you chose to re-pin the ECU connector instead of soldering

• Fine screw driver to remove pin from housing
• MQS Quadlock connector pair with atleast 2 pins
  • 2 pin male: Tyco 1-1718333-1 & female: Tyco 1-968699-1
  • 3 pin male: Tyco 1-1718346-1 & female: Tyco 1-968700-1
• another short piece of FLRy wire

Retrofit Additional +5V Output To ECU Plug

To have an additional +5V output available for the MAP (or basically any other) sensor you need to either modify the harness, or the ECU.

ECU modification is cleaner and cheaper but involves soldering on the PCB, for the harness mod you need an additional pair of connectors