Volkswagen Passat Forum banner

1 - 9 of 9 Posts

·
Registered
Joined
·
16 Posts
Discussion Starter #1
When I removed the MAF sensor to clean it today it seemed like there was a film inside of it and it smelled like gas. Is this a serious problem I need to figure out?

What could cause this? Thanks for any help guys.
 

·
Super Moderator
Joined
·
14,061 Posts
The PCV system lets gases back in that could do what you're describing I think.
 

·
Registered
Joined
·
5,514 Posts
Except the PCV vapor enters the intake tract downstream of the MAF, so the MAF should not have any fuel or oil residue. The MAF on the 1.8T is in the filter box, that for the 2.8 is separate but still fed only filtered air.
 

·
Registered
Joined
·
3,351 Posts
My money is on the fact that the PCV vents into the intake as well.
Also, if it's a 1.8t there is more than likely some oil in the intake plumbing, which would add to the oily gas scent.
 

·
Registered
Joined
·
9,797 Posts
I support what ylwagon said.
It is bad to have any film on the MAF, in a standard B5/5.5 no oil/fuel can be introduced upstream of the MAF.
(Note: If the combi valve remains open, exhaust can flow back into the filter box)

Do you have an aftermarket air filter ?
 

·
Registered
Joined
·
5,514 Posts
I suspect that Tom is asking whether you have an oiled-element filter, which is a well-known cause of malfunctioning MAF sensors.
 

·
Registered
Joined
·
16 Posts
Discussion Starter #8
No I believe it's not oiled element I got it from europarts.com I believe and was stated to be a specific replacement for VW's. C26128 Mann filter. Is that one ok?
 
1 - 9 of 9 Posts
Top