testing the maf sensor

[revlimit]

hi i am having trouble with my leon, have heard it could be the maf sensor.
how can i test it to see if it works. i have tried unplugging it but nothing happens, is this how it should be of should something happen when its unplugged.

many thanks

 

[VapourTrails]

i tried same thing when mine went but it didnt make a differnce only way to tell for sure is with a new one or a run on vagcom. it took a couple of runs with a new maf for it to be ok again maybe a run in or training period so unplugging it didnt do nothing.

what makes you think the maf is acting up?

 

[vwbassett]

When my MAF was faulty there was no real noticeable difference when i disconnected it. If it is fine like a new one there should be quite a difference removing it as the ecu goes from a level where it measures air -optimal to a ecu standard setting - sub optimal so should cough and splutter. If its an oldish car, never been replaced, with no fault codes dodgey running its quite like to be a MAF

 

[VapourTrails]

i assumed the same thing but my car ran same with and without the maf connected, yet when i put a new one on it ran perfect again. it was reading 70-80 max where it should have been reading 120-130.

 

[jiege01]

if its unplugged and there is no difference then the maf is buggered. the difference between a good maf and disconnecting it is clear as day.

 

[tonipieleanu]

i assumed the same thing but my car ran same with and without the maf connected, yet when i put a new one on it ran perfect again. it was reading 70-80 max where it should have been reading 120-130.

Shouldn't it be reading more like 140-150g/s on a stock car?

Mine is reading ~115g/s and I think is low and have to change it.

 

[JonLeonFr]

if its unplugged and there is no difference then the maf is buggered. the difference between a good maf and disconnecting it is clear as day.

I agree with above, i disconected mine and forgot to connect it back, jumped in and set of and thought i was in a 1.2 fiesta.


got out connected it back up and it flew again.

BIG BIG difference if the maf is working and dissconected.

 

[Shussain]

if its unplugged and there is no difference then the maf is buggered. the difference between a good maf and disconnecting it is clear as day.

Hi i have cupra 2008 i was wondering if u can help?, when mass sensor plug is connected its revs to 2500 and back down again it self , but when unplugged its revs normal but it doesn't boost fully thanks

 

[mty12345]

Hard to be 100% sure but it sounds like your maf could need replacing, however it could also be something like a large intake leak as unplugging the maf turns off a lot of the engine control features. The engine then runs in a kind of backup mode with the MAF unplugged, so this can make it seem like it's the maf when it's not. Code reader is the best way forward, that will point you in the right direction 99% of the time. Plenty of cheap ones on ebay etc atm.

If you do end up replacing the MAF, then it has to be a Bosch one. The cheap ebay ones don't work.

 

[Shussain]

Thanks for your info will do that

 

[Shussain]

Thanks for your info will do that

Also had this come up if it helps

 

[Jenk93]

Sorry to jump on your post but i have a 02 leon cupra its mapped and no matter weather my maf is plugged in or not the car runs the same ive put a new maf on it still the same car still goes well but is running rich getting about 16mpg in it anyone help?

 

[Legojon]

Sorry to jump on your post but i have a 02 leon cupra its mapped and no matter weather my maf is plugged in or not the car runs the same ive put a new maf on it still the same car still goes well but is running rich getting about 16mpg in it anyone help?

You scanned it for codes? Could be anything... O2 sensor, MAP sensor, bad remap. Also is it serviced regularly? Air filter, plugs, coils, etc?

 

[Jenk93]

Havent scanned it as of yet trying to find some one north east area with vagcom dont know much about seats always ran with vaux/ford