Cleaning the MAF

**sebasteeno** · Tuesday 8th December 2009, 12:09

Been told my car probably needs a new MAAF but i thought id try cleaning it first so what do i need to do, clean, look out for etc?

Any pics would be great folks?

Just a little pint too but if my mech says my car needs a new MAF does it just need a new sensor or the whole MAF?

**cameron** · Tuesday 8th December 2009, 12:20

Ive seen them being rinsed through with petrol before

Then left to thoroughly dry.

**sebasteeno** · Tuesday 8th December 2009, 14:04

Ive been reading up and a poster says to remove the top of the air box and spray carb cleaner into the MAF. Is this ok and would i do this with the engine running or not?

**cornclose** · Tuesday 8th December 2009, 14:05

No!

See here for a better idea of how to do it properly :-

http://www.louv.tv/cars/m5/MAF/

**Happygilmore78** · Tuesday 8th December 2009, 14:29

I followed a guide on my last MAF - knackered it even more. Got a brand new one for £60/£70 quid off ebay - ahhhhhh bisto!

**T5ER** · Tuesday 8th December 2009, 14:37

electrical contact cleaner is also usefull as it does not leave a greasy residue or film on the sensor itself which is what kills the sensor

**ncarnall** · Tuesday 8th December 2009, 15:10

I used brake & clutch cleaner and it's been fine since (about 3 months)

**Porcine_Aviator** · Tuesday 8th December 2009, 15:26

Take it off and spray WD40 through it. Don't touch the wire that's the sensor. Then put it back together. And run the engine.

This has worked for quite a few people.

If you are going to buy new get an OEM one the pattern ones tend to fail after a short time.

**T5ER** · Tuesday 8th December 2009, 15:29

i dont recomend wd 40 as it is oil based and oil kills a maf thats why you should never use one of those oiled cone filters, i found this out the hard way

**sebasteeno** · Tuesday 8th December 2009, 15:42

Is there any reason to buy a new MAF when it seems the part to clean or replace is the actual sensor itself?

**flyingbrick** · Tuesday 8th December 2009, 15:55

Hi Seb. Me thinks cleaning it aint going to do any good mate. I have been here myself and tyred the lot to clean it with no success. If ya think about it it does not get very dirty were it is. After the air filter. Have you had the car correctly diagnosed to make sure it is the mass air flow meter. If it is you will have to buy a new one buddy.......Like someone said in a earlier post it has a very sensitive air sensor on the part so cleaning it will prob make it worse...

**cornclose** · Tuesday 8th December 2009, 16:01

'Cleaning' it with WD40 will definitely make it worse. Don't do it!

**siamblue** · Tuesday 8th December 2009, 17:03

I have a spare here if you want me to send it up for you to try? it came off my V70 T5 00,

Gary

**sebasteeno** · Tuesday 8th December 2009, 17:15

Originally Posted by siamblue

I have a spare here if you want me to send it up for you to try? it came off my V70 T5 00,

Gary

That would be great Gary.

How much mate?

**T5ER** · Tuesday 8th December 2009, 17:15

is the 2.5 t the same maf as a T5 then ???? just curious more than owt

**Bob France** · Wednesday 9th December 2009, 00:18

On my truck[4:0 litre v6 ford]the engine was "bogging" badly and EML was on,I actually bought it with the light on.I found a site for cleaning the maf,and they used compressed air from an aerosol,[I could actually see the dirt on the wires] after cleaning,it was like driving another car ,fantastic, and, as a bonus tons more MPG.I would try a clean but be VERY careful with the sensor wire.If you can't find compressed air,try a small artists brush as they are super soft and won't damage anything that's what done the trick for mine,
anyway,you've got nothing ,to lose give it a go!!! good luck

**siamblue** · Wednesday 9th December 2009, 02:06

Originally Posted by T5ER

is the 2.5 t the same maf as a T5 then ???? just curious more than owt

Not sure i will get the part number off of it,

Seb just pay for the postage then return or buy it from me if it solves your problem then bingo,

Gary

**streaky744** · Thursday 10th December 2009, 20:12

to test if your MAF is working or not if the revs struggle then un plug it and the car revs as it should then its had it.

a lot of car go into limp mode when the MAF goes down and unplugging them does no long term damage (for purpose to see if it is past it) if you have no code reader to check it.

**sebasteeno** · Thursday 10th December 2009, 21:40

Originally Posted by streaky744

to test if your MAF is working or not if the revs struggle then un plug it and the car revs as it should then its had it.

a lot of car go into limp mode when the MAF goes down and unplugging them does no long term damage (for purpose to see if it is past it) if you have no code reader to check it.

The engine management light is on permanently and only stays off for around five miles when the code P1171 is erased. Once the light is on it runs much smoother. More recently its been running poorly all the time though.

**Quicksilver** · Monday 28th December 2009, 23:30

I thought I'd have look and see what all the fuss was about,I pulled the sensor out and found a layer of road grime along the leading edge of the blade, carefully cleaned it off with a cotton bud and white spirit.

Car run's great, two extra mpg and the odd stumble in revs I got at idle has gone.

I've replaced the security screws with phillips so I can take it out easier in future.