DME 405 IAT value map

Discuss Bosch (Porsche, BMW, Volvo, etc) tuning topics here. Request definitions, discuss parameters, etc.

Moderators: robertisaar, dex

Post Reply
Skeoph
Posts: 2
Joined: Mon May 01, 2023 9:29 pm

DME 405 IAT value map

Post by Skeoph »

Hi,
My MAF is dead on my M50b25 nv and a new one cost around 650€.. so i'm planning to swap it for a M54 MAF that is 55€.
My problem is, it's a 6 Pins MAF with air temperature sensor, so i need to change this value too in my file for the M54 ones.
I have the MAF adress map but not the IAT one.. if someone have it ?

Or maybe if someone have an alpha'n table tunned for stock M50b25 ? cause base alpha'n is very small and not for all RPM range..

Thanks
olafu
Posts: 186
Joined: Tue Jul 26, 2016 12:35 pm
Location: Finland

Re: DME 405 IAT value map

Post by olafu »

Header starts at 0x6F00, table starts at 0x6F0D. Problem is it's shared for coolant temperature sensor and air temperature sensor. Tables are identical between vanos engine and non vanos engine.
I think M50B25NV has no air temperature sensor in MAF. Air temp sensor is located under intake manifold like vanos engines.
NV engine has older "hot wire" type MAF. It needs regular cleaning and it's done by glowing the metering wire. These extra wires coming to MAF are for cleaning function. If i remember, DME cleans metering wire once of ten power off cycles.

---- EDIT ----
According some other information, DME cleans metering wire in every power off cycles.
Post Reply