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Cleaning the Mass Air Flow Sensor

The mass air flow sensor (MAF) senses how much air is coming into the engine. The DME uses this information to calculate how much fuel it should be putting into the injectors to maintain the proper air/fuel ratio. Over time, the tiny super sensitive resistor in the MAF can get dirty - this causes it to not detect the proper amount of air. This can cause erratic idle and loss of power and gas mileage. Cleaning the MAF is even more important if you've got a cold air intake with an oil filter - the oil will collect on the MAF. These instructions are for the factory intake.


Parts/Tools required: 10mm socket, flat-bladed screwdriver, CRC Mass Air Flow Sensor Cleaner spray, Lost Coast Brewery (Eureka, CA) Downtown Brown, bottle opener



Step 1: Disconnect the MAF wiring harness. I pulled up a little retaining clip slightly with a flat-bladed screwdriver to help me pull it out:






Step 2: Unscrew the two 10mm bolts holding the airbox in place. Use your flat-bladed screwdriver to loosen the hose clamp (complete removal is not required):





Step 3: Remove air box. To do this, you'll have to pull the snorkels out of both the inlet and exhaust of the airbox. After you've done that, rotate it up and toward you from the rear until it comes free. Some jiggling may be required.

Here's a picture of the airbox coming out of the car, with the MAF pointed out:






Step 4: With the airbox out of the car, you remove the MAF by using your flat-bladed screwdriver to pry these retaining clips out of the way (two of them, one on each side):






Step 5: Follow the directions on the spray. It tells you to spray the entire screen and sensor down with fluid 10-12 times, being extra careful not to touch the straw to any metal parts. After doing that, I held it until I couldn't smell the fluid anymore (that's my method of determining if it had all evaporated ). Replacement is the opposite of removal. Getting the airbox into place can require quite a bit of jiggling, so be patient. I haven't found any tricks, it just takes a few times to learn how it snaps into place. Be careful to pull your MAF wiring harness aside before placing your airbox into place. It sucks when you discover it's stuck under there.. (not that I'd know...).


 

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In the tube-everything in it.Doesn't matter if you soak the whole thing in electrical cleaner because it'll all eveporate and won't harm your electrics-We spray PCB's at work with the stuff all the time and they are very delicate and no harm has come to them........:thumbsup
 

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make sure its not a lubricant type cleaner aswell some are a switch cleaner which leaves a lubricating coating for switch contacts..

you dont want this all over your MAF meshing..

just an alcohol/solvent based cleaner no lubricants or anything else in it..
 

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make sure its not a lubricant type cleaner aswell some are a switch cleaner which leaves a lubricating coating for switch contacts..

you dont want this all over your MAF meshing..

just an alcohol/solvent based cleaner no lubricants or anything else in it..
reet is this the right one??

 
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