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MAf sensor bad?

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  #1  
Old 07-29-2010, 02:39 AM
HulkB5's Avatar
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Default MAf sensor bad?

So today i went ahead and bought a cone filter intake, and installed it in my car as i opened my airbox i found a almond still in its shell.
Thought id share that.
That was my wtf moment of the day.
So when i plugged the mad sensor in the car the car would idle way harder and the rpm at idle dropped up and down from 1500 back down to 500 almost killing the car.
it was impossible to drive my car around.
so i just left it unplugged.

Is that fine?
Should i get a new maf sensor?
What could this problem be!?
 
  #2  
Old 07-29-2010, 06:21 AM
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Have you checked to see if the MAf is installed correctly and not backwards?
 
  #3  
Old 07-29-2010, 08:22 AM
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what cone filter did you get? is it an oiled filter?
 
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Old 07-29-2010, 09:18 AM
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Hopefully its not the dreaded k&n...
 
  #5  
Old 07-29-2010, 09:53 AM
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Not like the K&N filter is going to kill the MAF before the car has even been started. Dont know why people think the filter is going to kill the maf when millions of car owners with maf's run the filters with zero issues. Just bad info passed on the web, just like that total BS about lucas oil additives from some bone head that has his own web site that just happens to be a dealer for another oil company.

I guess the people that believe BS web info also belived their parents when they said "if you keep doing that you will go blind and end up with hair on your palm" and still believe in the Easter Bunny, Tooth Fairy and Santa because people told them they were real. LOL

The maf was most likely installed backwards or he broke 1 of the wires while handling the maf harness which is going to have very brittle wires inside it seeing that it is 12 years old.
 
  #6  
Old 07-29-2010, 10:12 AM
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That said mike, ANY filter that has oil, on it, has been shown to be able to foul MAFs with in minutes after starting the car due to the oil sticks to the maf and then tiny particals of dirt then stick to the oil on maf causing bad readings. It's not the filter, it's oil that is sometimes more than needed on it. Not to mention if he found a almond in his airbox I'm guessing it might have been going prior to!
 
  #7  
Old 07-29-2010, 11:14 AM
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Originally Posted by joenelson7687
Hopefully its not the dreaded k&n...
I've had a K&N drop in for over 3 years with zero issues.
 
  #8  
Old 07-29-2010, 11:44 AM
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Originally Posted by chocalotstarfish
That said mike, ANY filter that has oil, on it, has been shown to be able to foul MAFs with in minutes after starting the car due to the oil sticks to the maf and then tiny particals of dirt then stick to the oil on maf causing bad readings. It's not the filter, it's oil that is sometimes more than needed on it. Not to mention if he found a almond in his airbox I'm guessing it might have been going prior to!
Yes if the air filter is saturated, problem is the maf is not saturated when it comes out of the box. That issue is caused by user error when the person cleans the filter using the K&N cleaner kit, then basically sprays so much oil on the filter to the point that the oil will not dry. When I worked at a Ford dealer we had a car come in and the person basically sprayed the whole can of oil onto the filter, basically oil was running off the filter when it was removed from the car. I bet that owner still blamed the filter for the maf going bad, but yet if he would have learned to read directions it would not have happened.

Fact is that K&N has shot down this already by building a machine that forced air thru their filter showing that no oil was coming from it.

I have actually been using K&N filters for well over 20 years, started running them on my turbo charged GST eclipse which we owned for 16 years. I also ran it in my Audi, ran one in my Titan which I owned for 4 years and that filter then went right into my new Titan. All of those cars run a maf and I only used 1 K&N Filter on each car, not 1 maf issue.


BTW the almond got into the part of the air box before the filter, this is because some people remove the small white screen that is on the air box opening for the inlet tube. Someone on another forum just posted a picture of his air box completely full of crap, but yet his car was still running. It was a funny thing to see.
 
  #9  
Old 07-29-2010, 04:40 PM
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Alright i purchased a spectre cotton fiber cone filter, Yes it is pre oiled.
And i installed the maf with the grated part away from the filter.
 
  #10  
Old 07-29-2010, 04:45 PM
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You have it backwards. Screen should face the filter. If you actually look at the maf body you will see a air which needs to point in the direction of the air flow which means it needs to point towad the turbo inlet hose and turbo, not toward the filter.


Here you can see it in this picture.


That grate side is the inlet of the maf, arrow is on the top part of that maf housing in the picture and faces the other direction.
 


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