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MAF Step-by-Step Cleaning Procedure with PICS

Badge767

SM 2010
SM 2009
Full Member
Joined
Dec 11, 2008
Messages
261
Location
38? 9'19.26"N *85?35'28.73"W *(Derby City!)
There are already several threads on MAF (Mass Air Flow) sensor cleaning, but I just did mine today, and thought I'd do a step-by-step photo essay of the process.

I bought a K&N drop-in air filter element, and decided to clean the MAF at the same time, to see if I can realize a bit of MPG increase like some others have reported.


OK, first things first: the MAF is located in-line within the duct that runs between the airbox and the throttle body:
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First step is to remove the wire connector from the MAF. A small gray retaining clip has to be remove first, using a small blade standard screwdriver:
232323232%7Ffp432%3B3%3Enu%3D3235%3E742%3E9%3C2%3EWSNRCG%3D323388%3C2%3A48%3A%3Bnu0mrj




It doesn't show in the above pic, but there's a small notch on the engine side of the clip you have to depress using the screwdriver blade, then the entire clip lifts straight up and off. Here's the clip removed:
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Now simply squeeze the black clip toward the wire end to release, and gently wiggle the connector off of the MAF:
232323232%7Ffp43332%3Enu%3D3235%3E742%3E9%3C2%3EWSNRCG%3D323388%3C2%3A7%3C9%3Bnu0mrj




Next step is to loosen the hose-clamp screw closest to the engine:
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Next, loosen the four TORX-25 screws that hold the airbox cover on (you can only see two of them in this pic):
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Now, simply lift up on the cover, and gently remove the duct from the engine-side of the MAF (photo shows post-removal):
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Here's the cover with MAF still attached:
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Loosen the hose clamp that secures the MAF to the cover and remove. DON'T drop it! The hot wire elements look quite fragile. If you look closely, you can see the three elements in this photo:
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I used CRC MAF Sensor Cleaner (available at any auto parts store):
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Just follow the directions on the can, and spray the entire grid area from both sides, and also the elements. DON'T let the straw contact the elements!

I left the MAF on my workbench to dry for about 20 minutes or so before reinstalling.


I've only driven about 5 or 6 miles around town today since I've cleaned the MAF, but my DIC reports (after a reset) an average of 16.9 mpg fuel economy during that trip. Prior to the cleaning, I'd average around 14.5 mpg or so around town
If it's really this easy to gain a few MPG, I'll be stoked, but I'm going to reserve final judgement until a few weeks of driving, and see what my DIC reports at that time.



 
I cleaned my MAF before going to KC  last week (first time I've every cleaned it) and performance and MPG increased.  Will do it more often, and I have 130,000 miles on my beast.
 
Well, I took my (almost) weekly trip to Frankfort today after my MAF cleaning (~150 miles round trip), and I did see an increase in fuel economy!  (y)


Previousvly, maintaining about 75 mph on this particular route (both ways) would yield only about 16.4 mpg.

Today, my average was 18.6 mpg!  :D

I was a little pressed for time, otherwise I would have maintained right around 70 the entire time, just to see what I could squeeze out of it.

Even at 75 mph, given the particular terrain that I traverse, I am still only turning around 1900 - 2000 RPMs, with the occasional steeper incline pushing me to around 2150 or so.

I'm guessing that maintaining around 2000 or less over the same course will give me close to 19.5 or 20 mpg, which I will be quite content with!

 
It does wonders for me too, engine runs much smoother nice write up Badge767
 
did it on mine this past weekend and my avalanche perform the same like before ,i guess because is 32000 miles, but my wife's  01 Aurora is like a new car , even with 75K miles , i guess it works on old but not old vehicles and maybe in some new models ,but anyways ,this works  (y) (y) (y)
 
I just recently did this as well...  Along with changing my fuel filter and cleaning my throttle body...  This completely cured my stalling out problem i was having and i got a good 2-4 more MPG...  (y)

Nice write-up Badge767...  (y)
 
I'm in the middle of cleaning mine right now. Couldn't get the harness off, but now I know to give it a little squeeze :beating:  Thanks for the write-up (y)
 
I just installed my K&N on my 2009, but didn't see the MAF.  Anyone know where it lives in the intake system on a 2009?
 
Just curious, how often should the MAF be cleaned? I'm creeping up on 30K on my 07, and I could use all the MPGs I can get.
 
From what I recall, the heated wires are monitored to how fast the temp cools when air rushes past them. This is one of the variables the fuel calculation computer uses to set how lean or rich the mixture. When dirt builds up on the wires  (older models or oil from the K & N filter) the cooling process takes longer resulting in a lean condition. Thus you are robbed of power and gas milage.

So an AV with only 30k miles and stock, probably would not see any difference after cleaning.
 
Z66Modder said:
From what I recall, the heated wires are monitored to how fast the temp cools when air rushes past them. This is one of the variables the fuel calculation computer uses to set how lean or rich the mixture. When dirt builds up on the wires  (older models or oil from the K & N filter) the cooling process takes longer resulting in a lean condition. Thus you are robbed of power and gas milage.

So an AV with only 30k miles and stock, probably would not see any difference after cleaning.

Sweet thanks. Coincidentally, my fuel pump went out, and had it replaced today by Chevy under warranty.
 
Talk about resurrecting an older thread!!

I sort of forgot about this post until today, thought I'd update:

I still regularly get around 19.6 mpg on highway trips when I keep the RPMs around 2K or less, which equates to right around 72 mph on level ground.

Prior to the MAF cleaning, I'd be lucky to get 17 under the same conditions, so I still contend that cleaning makes a noticeable difference!  (y)
 
Thanks for the reminder as it's been a while since I have cleaned mine.  (y)
 
I see on here some guys installed a spectre MAF what benefit does an aftermarket MAF give?
 
dfauerbach said:
I see on here some guys installed a spectre MAF what benefit does an aftermarket MAF give?

None, unless you are doing forced air induction.
 
Just cleaned mine. I think I will be doing this twice a year just to be safe.
 
I cleaned mine also yesterday and cleaned the CAI, it's like driving a new truck. :D
 
Morley said:
Thanks for bringing this thread alive again. I am willing to try anything to get higher than my 13.9MPG!

~Morley

Well, had a 3.5hr drive to the mother in law's. I reset the DIC before I left. When I got there, avg 60-65mph, avg mpg was 13! I cleaned the MAFS on Saturday.
Today's drive home, same speeds, gave me 14.5 mpg.

I will take anything with numbers this low.

~Morley
 
I just finished cleaning my MAFS and the difference is quite noticable. Thottle response is vastly improved and I'm looking forward to an increase in MPG. Thanks for the photos and instructions.

Easy little project to tackle and one of the best things I've done for my Av.
 
Im very happy I came across this one

I was going through my DIC the other day and noticed my MPG was at 12. My '07 is only at 42,000 miles and seeing my MPG's were that low when there are people saying they are getting 16 - 19 was a bit upsetting, granted its still cool here in Ontario but I wouldnt think it would affect the mileage that much ??

But after I came across this post I remembered after I got my "off lease" truck last July and I replaced the air filter shortly after and it was COMPLETELY plugged, I even had to clean up some dirt in the bottom of the air box. I am guessing my filter change in 2010 was the very first one.

I would bet this cleaning will help me big time !
 
I have came up with the code for my MAS and I will try this asap to see if this could be a big help considering with the K&N Filter on there as well.
 
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