my 03 plate vrs keeps blowing air flow meters its ok for a few weeks then it goes flat again un plug it and away it goes like stink again , when it goes flat the boost flutters when you put your foot down , any ideas folks , the car is fitted with a ko4 hybrid and its got a s3 maf fitted

can anyone help me on this

Could be oil contamination causing it. Have you tried cleaning the MAF's?

Other thought is, make sure to use genuine MAF's. Aftermarket ones are generally said to be a bit on the crap side.

i think it is oil but cant understand how its getting there and they are new bosch units

What air filter/induction setup do you have?

Steve

Maybe its isn't the maf at but the connector. Might have a loose wire in, broken connector, loose contact? It might beworth trying these broken mafs in another octy.

i think it is oil but cant understand how its getting there and they are new bosch units

What air filter are you using? some of the aftermarket ones have oil sprayed on them to help with filtration and if there's too much it can run off and end up putting a film on the MAF sensor - I had an ITG panel filter in but changed it back to standard after I noticed the green oil which was on the bottom of the filter had seeped up through the filter and was starting to show on top after a few weeks in use.

i think it is oil but cant understand how its getting there and they are new bosch units

Look at the breather system closely and all will become clear...

So, you could have a problem elsewhere causing there to be too much oil vapour in the air system. Hmm, now that's a bit more tricky.

im using the standard air box drilled with a pipercross panal thinking of fitting a catch can see if that helps , i dont think its a broken plug because its fine when unpluged ?

Put a paper one in...

what will that do ?

what will that do ?

The paper (OEM) filters don't have oil on them - so if the oil is coming from your pipercross filter this will address the issue.

Not if the oil is coming from the breather system it won't.

How is the oil vapour from breathe system going to go over maf???

P.s think about its location and wich way air is pulled before you reply ;-)

my panal filter isnt oiled ? so must be engine oil vapor but cant understand why its getting there

How is the oil vapour from breathe system going to go over maf???

P.s think about its location and wich way air is pulled before you reply ;-)

What about when you STOP the engine????

What oil vapour will rise up in the intake when engine is turned off??? Nope lol !!

Edited 15 September, 201114 yr by missingmyvrs

Have you actually measured the g/s readings with vagcom before you change the maf?

What oil vapour will rise up in the intake when engine is turned off??? Nope lol !!

You're viewing this with a narrow mind.

Imagine an engine that's breathing heavy, say perhaps worn piston rings, or rings that have gone soft. The engine will pressurised when off, and the vapour will want to go to ANY areas of lower pressure. There are many reasons why this could happen. Okay, so all of them mean engine trouble which may or may not be obvious. But it shouldn't be excluded outright.

Okay agree to disagree!! On all the 1.8t platform cars I work on not one has had a fail maf due to oil vapour from breather system!!! Oil from filters yes I have seen loafs.

will at performace torque told me the 1st one had gone because he had the car in because it felt slow , i fitted a brand new one and it was fine for about a month then flat again so fitted another new one thinking the other was faulty , and all was fine again for about 2 weeks now back to flat again un plug it and its away again ? the inlet system doesnt seem to have any abnormal amount of oil in it , would a compresion test show soft or worn piston rings the engine has only done 78k

will at performace torque told me the 1st one had gone because he had the car in because it felt slow , i fitted a brand new one and it was fine for about a month then flat again so fitted another new one thinking the other was faulty , and all was fine again for about 2 weeks now back to flat again un plug it and its away again ? the inlet system doesnt seem to have any abnormal amount of oil in it , would a compresion test show soft or worn piston rings the engine has only done 78k

Probably not, but it should be obvious to anybody familiar with the engines that it's breathing heavy just by removing the oil filler cap.

I seriously doubt this is the issue though.

Needs a little more thinking outside of the box.

I'm wondering where exactly have you drilled the airbox...

its drilled across the deepest edge about 12 holes