[Steadyhand]

I aim to 'refresh' my intake side with everything possible (e.g., new hoses, gaskets, CCV/PCV softball, DISA valves, MAF, filter, etc.).

I have researched here on e90post and found a couple of instances wherein someone claimed the N52 engines have both a MAF sensor and a MAP sensor (ostensibly located on the intake manifold towards the back. Other posts contradict this and claim only turbo models (N54/N55) have a MAP sensor.

Does the N52 have both sensors? (ECS does list a MAP)

[hassmaschine]

Yes. But there's no reason to replace the sensor.

[Steadyhand]

Fair enough. I understand what the MAP sensor does in the N54 (my son has a 2010 335xi).

I can't fathom what the MAP does for the 330i intake??

[hassmaschine]

It measures manifold pressure? There's still pressure/vacuum on N/A cars. Lots of non-turbo cars use MAP sensors.

[Terraphantm]

Technically it's a differential pressure sensor on the N52 (tells the DME the pressure difference between the manifold and the atmosphere). Combined with the atmospheric pressure sensor onboard the DME, and the end result is basically the same as a MAP sensor. With the MAF connected the DME won't rely on it too much, but without it it basically allows the DME to more accurately calculate engine load since the manifold pressure can drop below atmospheric.

[crashoverride]

My mechanic took out the after c02 sensor snaked up a camera and found a clogged Catalytic on the side I was having issues with... just a thought