330d Air mass readings

docwalker · 12-16-2012, 02:45 PM

Hi all

My 330d fuel economy has deteriorated, I have recently changed the egr and main stats and these helped a little and certainly improved the running temperature.

I also recent replaced the air filter which made a good difference to the drivability of the car.

So I bought and installed appropriate cable and INPA and my air mass reading is 1650

well outside the recommended range.

There was a number of codes also logged, including the air flow meter input air sensor

My question is what could cause this, is it likely to be a faulty maf?

Or is there out easier to check options than having to strip out half the engine to get to the maf!!

Cheers

Steve

docwalker · 12-17-2012, 02:24 PM

Hi

Quick update i cleared all the stored codes last night and rescanned tonight, all that remains is 6 glow plug errors which after some research points to a faulty control unit.

Air mass reading however is still too high. Could the glow plugs be connected to this or are they two separate faults?

Any advice would be greatly appreciated.

ade146 · 12-18-2012, 06:04 PM

High actual maf compared to expected is likely egr fault. Its turned down or perhaps stuck shut. If actual maf becomes too far from requested, expect an EML suggesting faulty EGR,

You can reset the adaptations on the maf should you wish. Make sure air flow is zero if you do.

docwalker · 12-19-2012, 02:00 AM

Hi ade

Many thanks for your reply

I guess that makes sense, I am a little surprised as the car feels strong at the minute (though that could be because I drive an E39 525i day to day and the 330d at the weekend, quite a difference in torque between the 2

)

Is it easy to get access to the valve to clean?

Cheers

Steve

ade146 · 12-19-2012, 05:51 PM

Yeah it come off from the front without removing anything else, although bottom bolt needs a flexi and bendy fingers. I always turn down my egr or partial blank on any car I have had. When I got the BM whatever I did threw a code relating to egr flow. In the end after multiple egr cleans plus testing I noticed the actual maf was nearly always higher than expected. Reset the maf adaptations and they now match which should now allow me to turn down the egr when I get around to it. My car is still running rich but I have also removed the dpf. it needs the zero load maps adjusted. In case you dont know the egr is very difficult to move. That vacuum diaphragm must have some proper force multiplication.

ade146 · 12-19-2012, 05:55 PM

Oh and the the egr isnt going to make any difference to how strong it feels. egr only occurs under partial throttle.

12-16-2012, 02:45 PM	#1
docwalker New Member 5 Rep 10 Posts Drives: E90 330D M Sport Join Date: Dec 2008 Location: Belfast iTrader: (0)	330d Air mass readings Hi all My 330d fuel economy has deteriorated, I have recently changed the egr and main stats and these helped a little and certainly improved the running temperature. I also recent replaced the air filter which made a good difference to the drivability of the car. So I bought and installed appropriate cable and INPA and my air mass reading is 1650 well outside the recommended range. There was a number of codes also logged, including the air flow meter input air sensor My question is what could cause this, is it likely to be a faulty maf? Or is there out easier to check options than having to strip out half the engine to get to the maf!! Cheers Steve
	Appreciate 0 Tweet Quote

12-17-2012, 02:24 PM	#2
docwalker New Member 5 Rep 10 Posts Drives: E90 330D M Sport Join Date: Dec 2008 Location: Belfast iTrader: (0)	Update Hi Quick update i cleared all the stored codes last night and rescanned tonight, all that remains is 6 glow plug errors which after some research points to a faulty control unit. Air mass reading however is still too high. Could the glow plugs be connected to this or are they two separate faults? Any advice would be greatly appreciated.
	Appreciate 0 Quote

12-18-2012, 06:04 PM	#3
ade146 Second Lieutenant 8 Rep 242 Posts Drives: E90 330d sport auto Join Date: Sep 2012 Location: S.Wales or Cheshire iTrader: (0)	High actual maf compared to expected is likely egr fault. Its turned down or perhaps stuck shut. If actual maf becomes too far from requested, expect an EML suggesting faulty EGR, You can reset the adaptations on the maf should you wish. Make sure air flow is zero if you do.
	Appreciate 0 Quote

12-19-2012, 02:00 AM	#4
docwalker New Member 5 Rep 10 Posts Drives: E90 330D M Sport Join Date: Dec 2008 Location: Belfast iTrader: (0)	Hi ade Many thanks for your reply I guess that makes sense, I am a little surprised as the car feels strong at the minute (though that could be because I drive an E39 525i day to day and the 330d at the weekend, quite a difference in torque between the 2 ) Is it easy to get access to the valve to clean? Cheers Steve
	Appreciate 0 Quote

12-19-2012, 05:51 PM	#5
ade146 Second Lieutenant 8 Rep 242 Posts Drives: E90 330d sport auto Join Date: Sep 2012 Location: S.Wales or Cheshire iTrader: (0)	Yeah it come off from the front without removing anything else, although bottom bolt needs a flexi and bendy fingers. I always turn down my egr or partial blank on any car I have had. When I got the BM whatever I did threw a code relating to egr flow. In the end after multiple egr cleans plus testing I noticed the actual maf was nearly always higher than expected. Reset the maf adaptations and they now match which should now allow me to turn down the egr when I get around to it. My car is still running rich but I have also removed the dpf. it needs the zero load maps adjusted. In case you dont know the egr is very difficult to move. That vacuum diaphragm must have some proper force multiplication.
	Appreciate 0 Quote

12-19-2012, 05:55 PM	#6
ade146 Second Lieutenant 8 Rep 242 Posts Drives: E90 330d sport auto Join Date: Sep 2012 Location: S.Wales or Cheshire iTrader: (0)	Oh and the the egr isnt going to make any difference to how strong it feels. egr only occurs under partial throttle.
	Appreciate 0 Quote