A Benz, a mass air flow sensor and tire dressing

I

imported_pdsterns

New member
I don't have all the details but my buddy has a late model Benz sedan and the dealer says that he contaminated his mass airflow sensor with his silcone tire dressing. The air intakes is in a front fender well, I have no details on the dressing, aerosol or jell, or anything else. Anyone ever heard this one before?
 
It may not necessarily be the dressing used, but could be the water that could have been sprayed on it 1st. Also, solvent based dressing can conduct electricity and short out electrical components. Having the air intact in the fender well doesn't mean much unless the car took in water driving through water. I don't think that's the case here or your engine would be hydro-locked. Either way, it sounds like a pricey repair. I'd price out a used mass air sensor(air flow meter) from Car-Part.com and have an independent garage install it for 1/2 the price.
 
General Motors had a Technical Service Bulletin delaing with owners of GM trucks, SUV's and H2's with MAF sensor problems to deny warranty claims if aftermarket air intakes were installed, especially K&N or other "oiled gauze" type filters.



It seemed that some customers would over oil their filters and the excess would be sucked in through the MAF sensor. It was probably GM's way of saving $$ and denying claims.



In your friends case, I dont see how excess tire dressing could be sucked through a fender intake and get passed an air filter.



Sounds like a service manager is trying to boost his numbers for the month to deny his claim.



Have him spray Quick Dry Electric Contact Cleaner over the sensor. That's how I clean mine.
 
Yal said:
Are they trying to deny warranty coverage?
Click to expand...



Well I think so from the way he talked, like $285 I think he said, sounded like they blamed him. How could they do that without some analysis of the contaminate on the MAF unit? I have to get back to him tomorrow and tell him about this thread and I will add more then. It was email conversation at end of day.
 
dealer BS pure and simple



Ask to see the air filter, if this was the case the air filter would be full of oil stains. Maybe oil could have gotten around the wire harness if he was doing an engine detail, but it is very unlikely he could get enough dressing in there past the weaterproof seals to short circuit it
 
I just watched a special on the Speed Network about K&N. Long story short; they (K&N) have NEVER found any of their oil in MAF sensor that their customers say caused it to go bad. If you have any questions about this, I’m sure you can go to the K&N site, or Speed Network and see if you can find the story.
 
Try getting the manufacturer of the dressing involved to see if they'll pick up some of the expenses or if they'd be willing to discuss cause and origin with the dealer. If they help offer then give them a plug here.
 
LouisanaJeeper said:
dealer BS pure and simple



Ask to see the air filter, if this was the case the air filter would be full of oil stains. Maybe oil could have gotten around the wire harness if he was doing an engine detail, but it is very unlikely he could get enough dressing in there past the weaterproof seals to short circuit it
Click to expand...



He is west coast guy and I am east coast but I will get more info from him later today but this was not an engine detail.
 
If it is to deny warranty coverage then I agree that it is total BS. A lot of the dealers are being squeezed every which way and some dealerships are going to come up with any excuse to deny coverage. The dumbest one I have heard so far is that clipping air freshners to the air outlets caused the hvac fan unit to fail:shocked But you would be surprised how many car owners would just say "Well darn, I guess i'll just pay then".



Have them prove it and don't be afraid to go over their heads directly to MBUSA. Or, try another dealership.
 
Yal said:
If it is to deny warranty coverage then I agree that it is total BS. A lot of the dealers are being squeezed every which way and some dealerships are going to come up with any excuse to deny coverage. The dumbest one I have heard so far is that clipping air freshners to the air outlets caused the hvac fan unit to fail:shocked But you would be surprised how many car owners would just say "Well darn, I guess i'll just pay then".



Have them prove it and don't be afraid to go over their heads directly to MBUSA. Or, try another dealership.
Click to expand...



So what was their BS on this, restricting airflow overloaded fan, you can close the outlet on the duct and that does not bother anything.
 
I've seen some stupid "I'm denying your warranty because of..." excuses, but this one takes the cake.



I would definitely revisit the dealer and ask to speak with someone higher.
 
Allright, the new guy can offer some insight and build the Post Count.



the MAF units are sensitive. However, I know quite a few people who have gotten around a replacement by pulling the MAF and cleaning it with CRC MAF cleaner spray.



Depending on which engine your buddy has will determine how tough the MAF is to get to.



Try the folks at MBWorld and his fellow car brethern can guid him in a bit more.



E
 
emrliquidlife said:
the MAF units are sensitive. However, I know quite a few people who have gotten around a replacement by pulling the MAF and cleaning it with CRC MAF cleaner spray.

E
Click to expand...



Exactly what I was going to suggest. Also, if it's really bad, you can take the MAF off, fill up part of a large plastic bag with rubbing alcohol, put the MAF in, and slosh it around to clean it all up.
 
Before he buys a new MAF sensor, he should take the sensor off (before the engine has started), spray the sensor liberally with electrical contact cleaner, let it air dry and reinstall. I had a similiar problem and followed the advice on another repair forum and saved myself several hundred dollars in a new MAF.
 
From the OP, I did not get the whole story originally so here it is, check engine light comes on, he reads codes with obd2 unit, indicates bad MAF and he goes and buys one and replaces it (benz was out of warranty). He later goes on net and reads how MAF can be contaminated and thinks he did it or might have some responsibility.



Anyway lots of good answers here and hopefully the thread has had some redeeming quality and will help someone out there.
 
You must log in or register to reply here.
Back
Top