Stutter at low revs

Johnanddonnamini said:

Hi all hope you can help.
Just bought a Mini Cooper d 2010 March and its got a stutter did some googling and then disconnected the maf sensor car then runs fine with maf unplugged thought yes I’ve found my fault so bought a new maf sensor fitted it and arghhh it still stutters at low revs. Confusing me as it runs perfect with maf unplugged but puts the engine light on. Really hope some of you can help.
Thanks
John

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seen something like this before customer had a lack of power issue and went online and found the disconnect the maff info done that then went on ebay and bought a maf sensor on price it even have a 5 year money back on it,, hmmm which he later found the maf must be fitted by a garage and give a garage bill for proof,,
short of the story was the cheap new maf was no good and caused the same issue ie out of spec as the resistances are not what the ecu needs to receive,, by disconnecting the maf the ecu automatically uses a set of preset fuel and running figures to keep car running, until the variable resistor ie the maf hot film or hot wire is back on line, the size of this wire must be perfect size and perfect wire make up to work correctly, the Chinese sourced ones are repo of the genuine thing and tend to either under fuel or over fuel or just not work,
genunie post march 2010 engine ie n47
https://www.ebay.co.uk/itm/Bosch-Ma...=264250473415b9fa3ee4c8ab43899939e823c61c0d5c
pre 2010 march psa engine
genuine
https://www.ebay.co.uk/itm/Pierburg...552262&hash=item23afd7d464:g:uyEAAOSw~XZb9~kN
IF THERES ONE SENSOR ON A ENGINE THAT MUST BE PERFECT ITS THIS IE MAF SENSOR.

Could it be that when the maf is unplugged it bypasses the egr valve I’m wondering if egr valve is sticking open as when I checked codes egr valve was there. Thanks for your reply mike just wanting to try other things before spending £3/400 on a dealer maf

Johnanddonnamini said:

Could it be that when the maf is unplugged it bypasses the egr valve I’m wondering if egr valve is sticking open as when I checked codes egr valve was there. Thanks for your reply mike just wanting to try other things before spending £3/400 on a dealer maf

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use the links above under £100 and genuine ones i included in the post, ten minute job to change over.
more than likely its a dpf filter/egr/soot build up in vnt of turbo is very common, need software to read it and see what is doing what, ie read the upstream and down stream pressure sensors for the dpf filter and maybe force regen or replace the filter, or send away to professional cleaners, a car with more than 75000 miles will be in the realms of this, best option is to diagnose it rather than hope, ie throw the cheapest part and hope that cures it.. and only way is diagnostics platform,, i recommend autocom cdp plus if doing it your self link below it will do all that and more dealer will lift £100-£300 for a scan and regen etc,
https://www.ebay.co.uk/itm/2017-Blu...135241?hash=item3d7bddc009:g:q1MAAOSw84ZcBUND

Problem solved !! Took all air intake off and airbox off and a all the bottom clips round the back were snapped so box wa sucking air in new clips on and fingers crossed just done 30 mile and no judders thanks for your help.