BMW M42 4 cyl
Choose M50 NON-Vanos : M42 harness is same, just some pins will be unused (4 cyl not 6cyl)
If you have any notable deviation, write details (pin / function) on this page, and we will investigate.
You can use the [M50 Non-Vanos] column as reference
- planning on removing the original AFM
- so I just need to connect the map sensor up to the inlet? just before the TB?
MAP is an abbreviation, => capital letters: Manifold Absolute Pressure
- Manifold, is by definition, AFTER the throttle, not before.
- think about it: how would the ECU know the MANIFOLD pressure if installed before the TB ? speed_density = RPM + Manifold Absolute Pressure based control;
- without turbo - NA - it would be possible to tune by alphaN=TPS , but tuning that is very laborsome;
- with turbo, removing AFM is OK, but MAP is needed !
- 6/4 pneumatic tube is normally used for MAP signal (the manifold always has nipple that can be used)
> wideband there is original wiring in the engine bay ?
Factory loom has too few wires. So small loom is provided (included) for the LSU4.9 or LSU4.2 (both have 5 wires; connector is different).
Which is best to use for my engine?
- LSU4.9 is more available, and will be more available in the future.
- it is said, that LSU4.9 is more durable during normal conditions
- however, some tuners say that under quite a bit of abuse, LSU4.2 can be more durable
- LSU4.2 is mostly ordered for compatibility (old installs with LSU4.2 connector - perhaps with old fw that would need work to be upgraded and verified/tuned)
- new installs normally use LSU4.9