Cleaning the MAF (MASS) Sensor

[Lin1952]

It was the crc MAF airflow sensor cleaner that I purchased/used.

[melba]

Reading through this thread it seems that people are getting the AIT ( air intake temp) sensor with the MAF. The Denso module contains both the AIT ( the bead object I see in everyone's pictures) and the MAF (the two tiny cylindrical shaped objects in the black tube)
Greg

so apart from cleaning the bulb (air intake temp) how do u clean the actual Maf sensor? Can u also spray down the two cylinder tubes?

[burnah]

Yep! I sprayed down the tubes as well.
http://www.newtriton.net/phpbb/viewtopic.php?f=23&t=8475&start=25#p202960

[wake jake]

Finally got around to cleaning mine today aswell as the unifilter. Hadn't cleaned it in a year haha and definetly does drive a lot smoother. Now to see if it uses less, great write up definetly will be doing it every few thousand kms.

[mIwoo]

I have been having issues with fuel economy and power. I have tried this today.... will see if it helps. Also, I think I might invest in a decent cotton filter... I was surprised how dirty my "new" filter was 3000 kms post service. For all HWY kms it was bloody filthy!

[antoo]

After reading this thread I also cleaned my MAF sensor and temp probe today.

Lately I had started getting the black smoke on take off and also worsening fuel economy.

The sensor had the same look as others on this thread and I've done 20,000 kms and half that time with a unifilter.

It is a bit anecdotal but my fuel economy seemed better today. I'll monitor it over the next few weeks.

[g4cube]

I did mine a few weeks ago and it seemed to run better and was easy to do how ever didn't do the temp probe antoo care to say where and how you clean it.

[antoo]

I thought I read earlier in this thread that the orange/brown blob thingy was one and inside the unit (down the open pipe end) there are two white bands that are the other.

No expertise here sorry.

[gregned]

The temp sensor is the blob thingy on the side.
You can clean it with the MAF cleaner spray and a rub won't hurt it as its an epoxy capsule.

[mIwoo]

Cleaned the probe and sensors and blew out my filter... seems my fuel economy is improving, i have more power in the lower rev range (< 2k) and its a lot more smoother.

[deermaster]

Brought the correct spray and took the sensor out. Mine was that dirty it was hard to tell there was an amber clear bulb underneath all that dust and gunk. Gave it a heap of sprays, it says on the can 15. They just want you to use it up faster I think. Anyway its clean like all the others now and the white bit inside is now white instead of dusty brown, even cleaned the plug sockets as they looked dirty too. A new filter seeing as I blew about a bucket of dust out the old one and it seems like it is running smoother, started easier and even seems to have more power.
Is this just a case of we think its heaps better because its clean? I know when I actually get around to cleaning my truck it always seems to run better and that's only cleaning the inside and outside, not the motor
I reckon being as dirty as it was though it would have to run better.

[DocBassett]

Hey guys, attempting this today, however I can't seem to unplug my little MAF unit from the wires?!?! Is there a special trick I am unaware of?!?! i don't want to yank and break something although i'm certain this is probably the first time it's ever been done so it may just be seized. Is it ok to spray with wires still in?!?!?!

[Cowboy Dave]

There's only that little tab on the top to squeeze? Should come off easy enough?

If the engine is off and the ignition off it would be okay I would have thought but I've always unplugged it because it's also worth making sure the contacts inside the plug are making a good connection (I used dielectric (sp?) grease).

[DocBassett]

yeah there was that little tab I was pressing down and I was pulling harder than a 14 year old boy that has just discovered pornography! so i just covered the engine bay in newspaper and sprayed away. It was pretty grimey. Has it made a difference...... i'm not sure. Also had a service today... so hard to tell.

[mostlyharmless]

Thanks to all who contributed to this thread. My 3.2 ML was struggling for power and surging. I changed the fuel filter but got no improvement. I changed the dirty air filter that hadn't been fitted properly at the service but that didn't help either. Then I read this thread and cleaned the MAF and things got a lot better. Over Easter I cleaned it again and also finally got round to fitting the EGR blank and things are better again but not perfect.

It feels better low down which I put down to the blank but the surging is not completely gone. I can and will clean the MAF again - it was pretty dirty. But I'm wondering should I be trying to clean the MAP sensor too? Has anyone done this?

Doing a bit of research, MAPs do seam to gunk up but there's not much on this forum about it.

Anyway thanks for the great info.
Cheers

[cnswilly]

I guess you can read this

http://www.doityourself.com/stry/3-map- ... ing-tips#b

[Froggy]

These sensors are very delicate and I would definately not be ignoring the instructions on the can and wiping them with a rag as that DIY article says.
Also, reading between the lines, it seems as if the author is in actual fact talking about the MAF sensor, not the MAP sensor.
IMHO some of the worst advice I've seen, but to be expected from that kind of website.

The MAP sensor measures vacuum/pressure in the manifold and is not exposed to air flowing past it carrying dust or oil from the filter. There is little need to clean it.

[Cowboy Dave]

I think I've heard that the hose to the MAP sensor can get a bit blocked though so maybe running a piece of wire through the hose to check that it's clear would be worth looking at.

On the MAF sensor, keep in mind that many of the images in this thread are actually of the temperature sensor which is on the same unit as the MAF sensor. The MAF is the tiny thing which is hard to see inside the plug thing whereas the temp sensor is the amber coloured item that appears to be covered in some sort of resin and gets noticeably dirty.

It's also worth cleaning the contacts in the plug itself with some contact cleaner and maybe using some dielectric grease or something to improve the electrical contacts in the plug. Some have suggested twisting the male points so they contact the female side a little better but I haven't tried that one myself.

[mostlyharmless]

Thanks for the replies. The article does seem a little confused about the difference between MAF and MAP.

I cleaned up the temp sensor pretty well tho the dirt probably doesn't insulate it much. I sprayed down into the MAF sensor too without touching the wires. It didn't take much to partially fill the housing with the clearer so I could swirl it a bit to clean the wires in the fluid but I was wary of overdoing it and damaging it.

I took a quick look for the MAP sensor but it wasn't obvious. I'll look harder, find that pipe and make sure it's free and I'll take a look at those contacts too tho they seemed reasonably clean and tight.

Thanks again

[cnswilly]

Yeah i didnt read it fully it was as i was walking out the door. Sorry for the confusion there. I have used lithium grease in the connectors before. (Currently running it in all my motorbike connections to prevent corrosion) No worries there. The contacts can be cleaned up just be careful with how much you take off if they are poor. I wouldnt twist them to much as it could cause further problems down the track. Clean the pipe is easy but being a pressure transducer i dont think you could really clean it to easily?

[furious]

I lost one of the screws that hold the MAF down. does any one know what kind of screw they are?

[mad992]

I lost one of the screws that hold the MAF down. does any one know what kind of screw they are?

HAVE YOU FOUND ONE YET MATE

i cleaned mine today but i could not notice much,maybe i was expecting like 5 more HP at the wheels like the can says
Hopefully Fuel economy will improve

[DocBassett]

Can anyone enlighten me, to help a mate- he has a petrol MK 2005 I think. Has lost some power and economy gone up after his mechanic oiled his paper K and N filter. Well we are pretty sure its a paper k&n. So filter has come out and I have suggested a clean of the MAF sensor. Is it the same deal/process as our cars? The unit is a lot bigger than mine and seems like it needs to be pryed apart with a flat head. Any contributions??

[AnOldFart]

Can anyone enlighten me, to help a mate- he has a petrol MK 2005 I think. Has lost some power and economy gone up after his mechanic oiled his paper K and N filter. Well we are pretty sure its a paper k&n. So filter has come out and I have suggested a clean of the MAF sensor. Is it the same deal/process as our cars? The unit is a lot bigger than mine and seems like it needs to be pryed apart with a flat head. Any contributions??

Sorry I can't help you with any details on the 'physics' of getting at/into the MK petrol MAF sensor Doc but from what you've described about "his 'mechanic' oiling the paper air filter" that's just the sort of thing that will cause problems 'dirtying' up the MAF sensor, courtesy of 'traces' of oil vapor now being inhaled through the filter and hence 'contaminating' the 'pristine' surface of the tiny and very sensitive, (and expensive) heated platinum wires that physically form the 'sensor' elements, and so, I'm pretty sure that you'll be on the right track with your ideas of giving it a clean up with the MAF spray.
The other thing to keep in mind Doc is that your friend will certainly also need to replace the now 'oiled' paper air filter as well, at the same time as you do the MAF clean, and also be sure to clean all possible residual traces of oil off the filter 'housing' as well.
If doing all of that definitely proves to cure his "loss of power and worse fuel economy" issues, then I'd certainly be hitting up "his mechanic" for at least, the cost of his 'new' replacement 'clean' air filter.

[Cowboy Dave]

Most of the K&Ns can be cleaned and replaced though. They look more like a paper filter than a foam filter like the unifilter but the one I had was still a fabric sort of thing rather than paper. I guess what I'm saying is that it's so unlikely that someone would be stupid enough to oil and non-reusable filter that it doesn't seem as likely as just over-oiling one that was able to be re-oiled. Hopefully that makes sense...