EGR air mass too high

[paprika]

So I'm still getting those code P0401 - air mass too high....car is a 2004 330d m57n

I cleaned the MAF and made sure that was ok, it's fine, and I replaced the EGR valve ( with a 2nd hand one of ebay that said working condition however can't guarantee this)







The above are pictures of the DIS system running tests however Im not quite sure what all this information means. What I can say is that the vacuum pipe is working and when the EGR valve was activated there wern't any leaks or anything however I couldnt hear it moving when the DIS said it was activating the EGR valve after every 4 seconds, I couldn't hear a thing, should I be able to?

ANother interesting thing, I chucked in Forte diesel stuff and the light went for about 10 tank fulls, ( it used to come on at least once every tank full and then the light would go itself off in that period), the light came back on and I chucked the Forte stuff back in, but this time the eml light is on alot more often.

The vacuum pipe deffo works asI felt the suction etc.

So how it stands :

cleaned EGR valve out just to clean much out as I read a DIY on here.
EML comes on
clean egr valve again, make sure everything fitted and oiled
light still on
replace egr valve with 2nd hand one off ebay
light still on
clean maf
light still on
chuck in forte
light goes for 3-4000 miles then comes back
chuck in more forte
light comes on more often
Indy has taken a look and cant see any obvious leaks or perished pipes
connect diagnostics for test

So chaps, what would you do?

[Moar]

May have potentially found the solution.

http://www.realoem.com/bmw/showparts.do?model=EX92...

Give no 17 a good clean, its the map sensor. Easy diy and bloody hell a massive different in low down pull etc.

Hoping this cures the air mass too high issue.

[brianbelfast]

Hi. I'm just wondering if anyone got to the bottom of this problem. I'm experiencing the same symptoms myself.

[1ronm4n]

Hi Chaps
Has anyone found a solid fix for this issue, @brianbelfast - i've noticed you've jumped on a few forums - did you ever get yours sorted?

I have an exhaust gas pressure sensor replaced at the tune of £137.60 and still not fixed!

Faults I have are:
290900: AIR SYSTEM, AIR TO EGR MASS FLOW PLAUSIBILITY: MEASURED AIR MASS IN
COMPARISON TO CALCULATED AIR MASS TOO HIGH

28DE00: EXHAUST GAS PRESSURE SENSOR BEFORE TURBINE, PLAUSIBILITY: EXHAUST
GAS PRESSURE BEFORE TURBINE DYNAMICALLY NOT PLAUSIBLE

Any help would be greatly appreciated.

BMW F30 2012 320d ED

[TurboRob]

Sounds like a sticky EGR valve to me - plausibility errors come from the measured value being too far from what the 'mapped' value should be.

[1ronm4n]

Hey TurboRob - I did get my mechanic to lube the EGR by removing the grey cap on the EGR - still having issues.

Edited by 1ronm4n on Thursday 19th September 12:31

[Ryan99]

Did anyone anger to solve the air mass measured too high fault?

[V8 Animal]

I have the same issue F15 X5
I’ve replaced the air mass meter but hasn’t solved it, I also get drive train fault that pops up but clears quickly normally when cold.
Have the engine light on now.
Booked it for a air leak test.

[V8 Animal]

I have the same issue F15 X5
I’ve replaced the air mass meter but hasn’t solved it, I also get drive train fault that pops up but clears quickly normally when cold.
Have the engine light on now.
Booked it for a air leak test.

[E-bmw]

V8 Animal said:

I ve replaced the air mass meter but hasn t solved it, I also get drive train fault that pops up but clears quickly normally when cold.

Did you replace it with a genuine sensor?

They don't like cheapo sensors.

Did you do any diagnosis or just swap the sensor as MAF air flow type errors are extremely rarely the sensor being the problem.

[rottenegg]

Air mass too high and air mass too low faults on BMW diesels is usually always caused by one or all of the following. It's very rare it's the MAF sensor itself, unless it's a crappy aftermarket one.

Sticky/stuck EGR valve
Blocked EGR cooler
Blocked pre-turbine pressure sensor tube