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map sensor
Posted: Thu Aug 02, 2018 8:00 pm
by X5Andym
Hi ALL
Please can I ask for some help and advice.. I have a E53 4.4 X5 petal, year of reg 2005.. with very low mileage.. 38000, but having a few problems... O:-)
I have change the spark plugs, HT coils all eight, the fuel filter and the ignition rely, but still have a problem that the car stalls when not moving some times, sometimes, then miss fires across the ports/cylinders when I try to restart the car..?? restart then seems ok.. looked on line and points to the map sensor may be the problem and need replacing... has any one had the same issue.. and can give me the part number of the map sensor, did ask euro parts but they need the part number :'(
Thank you very much
Cheers
Andy
Re: map sensor
Posted: Thu Aug 02, 2018 8:08 pm
by Horizon
Go on real OEM and put the last 7 digits of your VIN in the box and look under fuel system that will give you the VMW part number cross reference with ECP
Have you tried it with the MAF disconnected ?
Re: map sensor
Posted: Thu Aug 02, 2018 8:32 pm
by X5Andym
Hi mate
Thank you for your rely.. I am no mechanic at all.. so no have not tried with the MAF disconnected, as I do not know, what the MAF IS.. where do I find the real OEM...
thank very much.
Cheers
Andy
Re: map sensor
Posted: Thu Aug 02, 2018 8:59 pm
by X5Sport
Realoem.com. Copy of the real BMW parts system.
MAF = Mass Air Flow Sensor. The device that tells the engine how much air is going in and it’s density (hence mass).
You would be well advised to have a code read done - either by BMW or a good independent garage - to see what actual faults are being logged. You will end up chasing a rabbit down a hole otherwise, and that gets tedious and expensive.
And

Re: map sensor
Posted: Thu Aug 02, 2018 9:07 pm
by X5Andym
Cheers will do... I have pushed the button on the dash.. show.. all control ok..?
Will take your advice... but got to get the garage.. without causing a problem..
Cheers
Andy
Re: map sensor
Posted: Thu Aug 02, 2018 9:10 pm
by X5Sport
The button on the dash tells you very little. Only a dump of the error logs will tell you (or any decent garage) what to look for.
If you have a member nearby with the Carly systems (Android/iOS App and either Bluetooth or WiFi adapter), or a copy of the BMW software, and who is willing to help diagnose, you can see if anyone is around.
Re: map sensor
Posted: Fri Aug 03, 2018 10:35 am
by V8 00USH
Hi Andy
You do not have MAP sensor however you do have a MAF sensor.
You find it here - item 1 in the below diagram
https://www.realoem.com/bmw/enUS/showpa ... Id=13_1033
Simply unplug it and try using the car without it plugged in - if it improves the situation then chances are it's this at fault. Also bear in mind that vacuum and breather issues can also have similiar symptoms.
Re: map sensor
Posted: Fri Aug 03, 2018 7:06 pm
by X5Andym
Hi Thank you for your help.. looking at the attached the plug is item 9.. do you mine unplug that..
Cheers
Andy
Re: map sensor
Posted: Fri Aug 03, 2018 7:44 pm
by X5Andym
Mass air flow meter.. I had the same problem.. on my Astra 2.0 16v GTE.. a number of year ago.. change it.. all was good.. will do the same.. on my 4.4.. cheers..

Re: map sensor
Posted: Fri Aug 03, 2018 8:01 pm
by X5Andym
??? would a fault with my mass air flow meter cause misfiring across the ports/cylinders and cut the engine when not moving..
Cheers
Andy
Re: map sensor
Posted: Fri Aug 03, 2018 8:43 pm
by X5Sport
It certainly can do as the engine is getting inaccurate air data so the mixture is wrong. The ECU will then ‘guess’ at the right fuel ratio and if too rich or lean, the engine misfires or stalls. Disconnecting it puts the system into a default setting which although not perfect will let you prove the point.
Re: map sensor
Posted: Sun Aug 05, 2018 10:34 am
by X5Andym
Sorry more help on this please, I have tried to unplug the plug from the MAF sensor, but cannot move the plug, how is this done, It seems to be lock on.. ?? is it just a push fit which I need to get some grips on..
Thank you very much
Cheers
Andy
Re: map sensor
Posted: Sun Aug 05, 2018 11:34 am
by Alan Gunn
There should be a small tab you press on and pull at the same time.
Re: map sensor
Posted: Sun Aug 05, 2018 2:55 pm
by X5Andym
Hi AGAIN..
Sorry to continue with this, my MAF sensor looks like its the fault, now looking buy a new one, but which one, looked on e-bay quite a lot and different pricing, also looked on you tube, which made things worst, the cheaper sensors seem the way forward and not the top price ones, has any one change there's, on a 2005 4.4 petrol and can advise a part number of the best MAF sensor..
Thank you all again...
Cheers
Andy
Re: map sensor
Posted: Sun Aug 05, 2018 3:19 pm
by henrym3
Eurocarparts might be worth a look they got 37% off this weekend. They normally do BOSCH but your still probably looking £150