barto125

Hello! I'm new here. Hope that somebody can help me with my MB.
Its w202, c280 M104 engine.
I rebuild throttle and ECU wiring, but still have some problems.
From HFMscan:


010, Post, ACTUAL
Air mass flow meter : open circuit.

Voltage at hot film (IGNITION=ON, and temp. > 70řC) : 0,8V-1,1V.
Voltage at voltage supply : 11V-14V.
Increasing engine speed = increasing voltage.
Verify also the cable insulation : > 20 KOhm,
and the ground cable.
__________________________________________________ ___________
036, Post
Lambda control is at lean stop : mixture too rich.

Unmetered air, fuel injection valves, diaphragm pressure regulator.
!!! With TWC !!!
__________________________________________________ ___________
099, Post, ACTUAL
Fault in CAN communication from EA or CC control module.

Verify module, and replace if necessary.
Internal Resistance : 115-125 Ohm.
__________________________________________________ ___________
104, Post, ACTUAL
Safety fuel cut-off from electronic accelerator or CC activated.

!!! Only with EC or CC !!!
except USA J, 202, 210 USA.
Verify fuel cut-off control from EA actuator, CC actuator.
IGNITION=ON -> voltage jumps : 2,2-11V.


Don't know why there is Air mass flow meter : open circuit, I checked wiring and everything is good from ecu to maf sensor.

Any ideas?

mercedes211995

did you manages to get the problem fixed? becuase
i am having very similar issues. i replace MAF, O2 sensor, the car has new wiring harness. i think it is because the voltage is not stable or low. i will be looking at the voltage regulator and seeing if that will fix it.

please keep me posted.

mercedes211995

FIXED IT.

hair line crack at the vacuum manifold vacuum manifold. also, the previous mechanic decided to swap the pins for the MAF, that is way it always faile.

superglued the crack, put the pins in their correct order and surprise surprise it works perfect. will drive it tomorrow to work with a big smile.

thanks everyone.