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Anyone ever cleaned their MAF?


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I was just wondering if anyone has ever cleaned their MAF and if so, what did you use? I was told to use starting fluid because it is alcohol based, but I am under the impression that it would damage the MAF. If anyone can shed some light on this topic, I would very much appreciate it.

 

Thanks in advance.

 

Sincerely,

Patrick

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The hotwire MAF is a self cleaning unit. every time the car shuts down, it momentarily superheats to burn the crap off the filament.. thats why its called a hotwire. I don't know the exact temp of a soob, but the average is approximately 1500 degrees for a split second.

 

An old vane type (85-86) can stand a good cleaning, but 87+ have no moving parts, nothing to get stuck and the part that does all the work is self cleaning.

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that is unless you pull one off a car that is black with oil - then you clean it !!

realizing all of them are well over 10 yrs old, a cleaning would not hurt.

If its covered in oil, you have more problems than just your MAF. Especailly considering the MAF in no way comes in contact with any part of the oiling system of the car.

 

I have 4 in the garage right now and there is no appreciable crap build up on them. I have yet to see a hotwire MAF of any kind that has benefitted from being cleaned.

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Brake fluid is best because it leaves no residue.

That's how I cleaned mine!

mabey you meant brake cleaner? brake fluid is nasty stuff.

 

caleb is right for the most part. they are self cleaning. and you should not have any oil in the MAF for any reason.

I have needed to clean them due to a failed paper air filter alowing stuff thru. all it takes is a squirt at the elment and you are all good. brake cleaner or throttle body/carb cleaner work well.

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^^right.. if you don't believe me, listen to Russ.. he knows his stuff.

every time I learn more I just realize how little I know.

 

for the most part our mafs are ok. ford is where I learned about the clean the maf trick. they do not have a burn off (mabey new ones do). lots of problems there. usually come in with new O2 sensors installed by someone and lean codes set in the computer. a squirt and a memory reset and its all good till they get dirty again.

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The car I got my MAF off of had slipped a ring, so there was oil EVERYWHERE, but I had no other alternative. (EA82 parts are not common near my home)

Yes, brake fluid is VERY nasty stuff, but it brakes down oil effectively and leaves no residue (would cause big problem).

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They make a cleaner specifically for MAFs (different than the carb/throttle body cleaner), check at the parts store. I used it to clean mine a while back, I didn’t notice any performance change, but it looked pretty clean before and I wasn’t having any real trouble. The “hot wire” itself is pretty delicate so don’t go blasting away with the garden hose or blowing off with compressed air.

 

The hotwire MAF is a self cleaning unit. every time the car shuts down, it momentarily superheats to burn the crap off the filament.. thats why its called a hotwire.
BTW, I’m not sure if the EA82 has the “burn off” feature but it might (mentioned in the FSM?). But that’s not the reason its called a hot wire MAF, the wire is heated in normal operation and the air flowing past it cools it and changes its resistance and the output signal voltage. The actual device is called a “hot wire anemometer”.

 

Gary

 

Definition borrowed form here: http://www.tpub.com/content/doe/h1013v1/css/h1013v1_100.htm

Hot-Wire Anemometer The hot-wire anemometer, principally used in gas flow measurement, consists of an electrically heated, fine platinum wire which is immersed into the flow. As the fluid velocity increases, the rate of heat flow from the heated wire to the flow stream increases. Thus, a cooling effect on the wire electrode occurs, causing its electrical resistance to change. In a constant-current anemometer, the fluid velocity is determined from a measurement of the resulting change in wire resistance. In a constant-resistance anemometer, fluid velocity is determined from the current needed to maintain a constant wire temperature and, thus, the resistance constant.

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I am NOT talking about brake fluid, that would definately cause problems, I am talking about brake cleaner, it is in an aerosal can and is rather caustic (use in a VERY well ventalated environment)

BTW - I am 90% sure that at least the SPFI cars do not have the burn-off feature. There is no mention of it in the FSM, and I can see no evidence of it on a dirty MAF sensor, so cleaning it is probably a good idea.

All-talk is also right about how the MAF sensor works, so keeping it clean is important, but it should not usually require cleaning.

I got my MAF out of a junkyard car, the ENTIRE intake, exhaust, and all other systems were soaked in oil (and I was told it had little/no compression when junked), but it was all I could find, and I needed an MAF.

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subaru MAFs DO have a burn off cycle.

I have measured it on my graphing meter. right after the car is shut off it lights off for a few seconds then its done. its a very simple cleaning method. works well on organic material. not so well on dirt ect.

thats where you may find the need to clean your MAF. I use brake clean(not brake fluid) because its cheap and as stated leaves no residue. you can by the expensive MAF stuff but I really dont think there is much difference.

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Starting fluid is basically either, highly intoxicating AND explosive! Use in a WELL VENTILATED area! Perhaps a better solvent is Berryman's Chem-tool

 

 

 

I was just wondering if anyone has ever cleaned their MAF and if so, what did you use? I was told to use starting fluid because it is alcohol based, but I am under the impression that it would damage the MAF. If anyone can shed some light on this topic, I would very much appreciate it.

 

Thanks in advance.

 

Sincerely,

Patrick

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I'm glad you asked that! I was wondering the same thing myself. Now, I wonder if my 84 GL/EA81 has one.

 

Jon

unless your car is fuel injected, it doesnt have one.

 

SPFI hotwire MAFs dont have burn off, MPFI ones do. I think thats how it goes. I think the SPFI MAF is an aa100, and the MPFI is an aa110 if these numbers are correct than I should be correct on the burn off feature.

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