Mass Airflow Sensor

How many of you have cleaned your MAS (Mass Airflow Sensor) lately? The
other day my MIL came on. The code was p0171. (lean on bank 1 sensor
1). Well after looking around on the Internet I came to a conclusion
that I should try cleaning the MAS. Well after I cleaned it my truck
(96 4x4 Tacoma) ran like a freakin' race car. The previous owner had
replaced the exhaust with a better one and I'm using a K&N air filter
but the truck was just running like crap. It's the first 4 cyl that
I've had in a long time I just blamed the poor performance, and delay of
power on the size of the engine.

Just curious if anyone else has seen this happen. I can't imagine how
many people are driving with dirty MASs and not realizing the difference
it makes.

For anyone that wants to try it I just used brake cleaner because it's
fairly clean and doesn't leave any type of residue. Also, if you try
it, make sure that you are cleaning the tiny little wires inside of the
MAS. Some people mistake some of the external parts of the sensor for
these wires.... (Mine was really obvious).

Anyway, I'd like to hear what kind of results others see from cleaning it.

Good luck,
Dante

"Dante" <dante@xmission.com> wrote in message
news:eiahcp$2dh$1@news.xmission.com...[color=blue]
> How many of you have cleaned your MAS (Mass Airflow Sensor) lately? The
> other day my MIL came on. The code was p0171. (lean on bank 1 sensor 1).
> Well after looking around on the Internet I came to a conclusion that I
> should try cleaning the MAS. Well after I cleaned it my truck (96 4x4
> Tacoma) ran like a freakin' race car. The previous owner had replaced the
> exhaust with a better one and I'm using a K&N air filter but the truck was
> just running like crap.[/color]

<snip>

Dante,

Crudded up MAF sensors are a hazard with the K&N system. Although K&N
swears that there is no connection, they predicate their assertion on
properly oiled, serviced and installed filters. If the consumer - you -
overoils, doesn't install it properly, or fails to service at the
recommended intervals it leads to dirty MAf sensors and in all likelihood
increased engine wear.

Please note that K&N advertises improved performance, not improved
filtration, reliability or engine life.

My two cents.
--
Mike Harris
95 Tacoma 2WD 2.4L
Austin TX

"Dante" <dante@xmission.com> wrote in message
news:eiahcp$2dh$1@news.xmission.com...[color=blue]
> How many of you have cleaned your MAS (Mass Airflow Sensor) lately? The
> other day my MIL came on. The code was p0171. (lean on bank 1 sensor 1).
> Well after looking around on the Internet I came to a conclusion that I
> should try cleaning the MAS. Well after I cleaned it my truck (96 4x4
> Tacoma) ran like a freakin' race car. The previous owner had replaced the
> exhaust with a better one and I'm using a K&N air filter but the truck was
> just running like crap. It's the first 4 cyl that I've had in a long time
> I just blamed the poor performance, and delay of power on the size of the
> engine.
>
> Just curious if anyone else has seen this happen. I can't imagine how
> many people are driving with dirty MASs and not realizing the difference
> it makes.
>
> For anyone that wants to try it I just used brake cleaner because it's
> fairly clean and doesn't leave any type of residue. Also, if you try it,
> make sure that you are cleaning the tiny little wires inside of the MAS.
> Some people mistake some of the external parts of the sensor for these
> wires.... (Mine was really obvious).
>
> Anyway, I'd like to hear what kind of results others see from cleaning it.
>
> Good luck,
> Dante[/color]

The sensor is generally referred to as a MAF (mass air flow) or MAP
(manifold absolute pressure) sensor. The hot wire type MAF sensor can get
dirty and act as an insulator so that the air flowing past the wire doesn't
cool the wire enough. The MAF sensor is supposedly not serviceable, but
IMO, it is worth trying to clean it before replacing it. I would use
rubbing alcohol instead of brake cleaner because the rubbing alcohol is not
quite as harsh.

In order to achieve the higher air flow, many aftermarket air filters let
more fine particles pass than OEM filters. A consequence of the fine
particles passing through the filter are dirty MAF sensors, oil that becomes
contaminated more quickly, and more engine wear. The aftermarket air
filters that use an oil bath or coating of oil also contaminate MAF sensors
from the oil vapor, which is why you do not see that type of filter OEM
applications.
--

Ray O
(correct punctuation to reply)

: The sensor is generally referred to as a MAF (mass air flow) or MAP
: (manifold absolute pressure) sensor. The hot wire type MAF sensor can get
: dirty and act as an insulator so that the air flowing past the wire doesn't
: cool the wire enough. The MAF sensor is supposedly not serviceable, but
: IMO, it is worth trying to clean it before replacing it. I would use
: rubbing alcohol instead of brake cleaner because the rubbing alcohol is not
: quite as harsh.
:
: In order to achieve the higher air flow, many aftermarket air filters let
: more fine particles pass than OEM filters. A consequence of the fine
: particles passing through the filter are dirty MAF sensors, oil that becomes
: contaminated more quickly, and more engine wear. The aftermarket air
: filters that use an oil bath or coating of oil also contaminate MAF sensors
: from the oil vapor, which is why you do not see that type of filter OEM
: applications.


What about carb cleaner in the spray can?

"Watts D. Matter" <qwerty@cox.com> wrote in message
news:rF42h.2$3K7.1@newsfe13.phx...[color=blue]
>: The sensor is generally referred to as a MAF (mass air flow) or MAP
> : (manifold absolute pressure) sensor. The hot wire type MAF sensor can
> get
> : dirty and act as an insulator so that the air flowing past the wire
> doesn't
> : cool the wire enough. The MAF sensor is supposedly not serviceable, but
> : IMO, it is worth trying to clean it before replacing it. I would use
> : rubbing alcohol instead of brake cleaner because the rubbing alcohol is
> not
> : quite as harsh.
> :
> : In order to achieve the higher air flow, many aftermarket air filters
> let
> : more fine particles pass than OEM filters. A consequence of the fine
> : particles passing through the filter are dirty MAF sensors, oil that
> becomes
> : contaminated more quickly, and more engine wear. The aftermarket air
> : filters that use an oil bath or coating of oil also contaminate MAF
> sensors
> : from the oil vapor, which is why you do not see that type of filter OEM
> : applications.
>
>
> What about carb cleaner in the spray can?
>[/color]

Aerosol carb cleaner should be OK, but it would be my second preference
after rubbing alcohol. My thinking is that since you are not supposed to
use anything on it, if you do choose to give it a try, then use the least
caustic stuff available. Also, carb cleaner can leave a film where rubbing
alcohol does not.
--

Ray O
(correct punctuation to reply)

Ray O wrote:
[color=blue]
>Also, carb cleaner can leave a film
> where rubbing alcohol does not.[/color]

The usual rubbing alcohol (70%) can contain additives such as glycerin.
It would be better to use 90% alcohol - easily available at Wal-mart.


---MIKE---[color=blue][color=green]
>>In the White Mountains of New Hampshire
>> (44° 15' N - Elevation 1580')[/color][/color]