Too much cleaning of Mass Air Flow sensor?

These are wear parts, and it's not that expensive to replace. Amazon has them for about $70. There's only 2 screws holding it, takes about 5 minutes to do.

 

This is why I will always come to Priuschat first before I either work on my car or take it to a dealer.

 

Don't know about the "tale they told you." It sounds like BS, but $117 labor for something that takes about seven minutes to swap out....

 

.
If you are replacing the MAF, consider a new O-ring (90099-14141). If needed, new screws (90167-A0016). From any Toyota source for about $5.
.
My new MAF didn't include either.
.
. . . . I tried removing and cleaning the old MAF with the CRC MAF spray cleaner but still had issues. New MAF installed in minutes; no issues.

 

Of course, this company makes the cleaner....but....


CRC Industries, Inc.
1/12/2006
Technical Brief
Subject
:
.........
Why should the MAF sensor be routinely cleaned?
A dirty MAF sensor hot wire may cause many problems including difficult starting, poor accelerations, pinging, rough idling, loss of horse
power and a decrease in fuel economy. CRC recommends the sensor be cleaned every time the air filter is replaced.
How do you clean the Mass Air Flow sensor?
1.
With the engine off and cool, locate your MAF betwe
en the air box and throttle body.
2.
Unplug the MAF wire harness and then remove the hou
sing. (Typically a screwdriver will
work or you may need a T-20 TORX® Security bit.)
3.
Place a shop towel or rag under the MAF housing to
catch any run-off. With straw
attached to nozzle, apply 10-15 sprays of
CRC Mass Air Flow Sensor Cleaner
onto the
hot wires or hot plate and thermistor inside the ho
using making sure all sides, wires and
connectors are also cleaned.
4.
Reassemble the MAF and allow to thoroughly dry befo
re reactivating.
5. For optimum performance, clean the MAF sensor ev
ery time the air filter is cleaned
or replaced.
Why should you use Mass Air Flow Sensor Cleaner ins
tead of a general purpose
degreaser or cleaner/lubricant?
CRC’s Mass Air Flow Sensor Cleaner
has been developed to clean all of the road type s
oils
found in the sensors without harming the sensitive
plastics or leaving a residue on the wires or
plates which will decrease engine performance. Most
general purpose degreasers will adversely
affect plastics, rubber o-rings and painted parts w
hile
CRC’s Mass Air Flow Sensor Cleaner
will not. In addition, it evaporates quickly and co
mpletely without leaving any residue.
With Frequent Cleaning of your vehicles MAF sensor
what benefits would you expect?
Improved performance and reliability of the Mass Ai
r Flow sensor can lead to improvements in
the vehicles Air/Fuel ratio, horsepower and MPG.

 

And that doesn't benefit CRC in any way at all.

 

Know exactly what you are saying, and I would never clean that often. Heck, my Camry, I first cleaned the MAF at 145K and then at 165K and all is well with it (I did a so-so job at 145K)..

The Prius was having issues at 73K, so cleaned it then and all is well. The part is == as someone said == a "wear part" and it would not be unheard of to replace it, but I have never heard the cleaning more than twice bit....

 

The OP post is one of the first times I have heard of such numerous cleanings.
Unknown if the cleaning actually caused the failure and exactly what failed in the MAF.

Yes, that wire is fragile.

Sure, CRC company would say to clean often (and buy more product).

Conservatively, I could agree with the dealerships comments.

Yet what causes a MAF to get dirty?
PCV smog system introducing oily air to the throttle body tunnel?
Dirt leaking from the air filter or K&N filter oil?
Not sure if there is preventative techniques to keep the MAF super clean.
Plus again what actually failed?

Based on this post, seems that every 75K cleaning could be called for if Prius owner is OCD.
(3 or 4 cleanings over a 300K life.)
Or once every 100K under the "if it ain't broke..." philosophy.
I think 100K would be my recommendation.

FWIW I have found the throttle body "butterfly" area the area that could use cleaning ever 30K on other makes of cars.

 

Man the op is got some ocd about the maf. He caught it here. This site has so many posts about cleaning the maf. Holy Cow.
So much bullshit on this site.

Look if the maf has any issue at all it will instantly throw a check engine light. Maf is a highly monitored device. Don't touch the freaking thing. I'm at 100K miles since new and I have cleaned it once and even then it was clean and I regret touching it. I can't remember ever cleaning a maf on any other car I've owned. There very fragile.

You want to help your car change the oil...change the trans fluid..change the Inverter coolant. All a good bang for your time and $$$.

 

I did some maintenance and repair work on my daughter's 2007 (90K miles) this past weekend. I noticed the amber bulb which has the air temp sensor was dirty so I removed the MAF sensor for cleaning using the CRC MAF cleaner spray. Since the greyish deposits were on top of the bulb only, I assume the problem was dirt leaking in around the engine air filter. The air flow sensing wires looked OK but I gave them a few sprays anyway. This was the first time the MAF sensor had been cleaned on this car.

I also cleaned the throttle body interior. Rather than drown the throttle body in cleaner which is what the cleaner manufacturer would have you do, I use Q-tips moistened in 91% isopropyl alcohol.

 

my .02 from owning many cars and doing lots of maintenance myself.
dont bother cleaning the MAF unless its obvious you just coated it with oil from some mistake on another part.
for example installed a cold air intake with an oiled K&N filter and the oil from the filter sucked into the intake and slimed your MAF,
not likely to happen on a prius since nobody installs a CAI on a prius.
or you were trying to fog your engine, or suck in some seafoam to decarbonize... and somehow squirted it onto the MAF.
in any of those cases, the MAF will quickly malfunction and engine light will come on and codes will be thrown.
only in one of these very specific cases is a clean worth attempting.
there is NO other reason to try to clean the MAF, EVER.
if it fails at 90k replace it
if it fails at 145k replace it
if it fails early at 50k replace it and try to figure out what possibly could have killed it that early.
replacing a MAF is really really easy, i have never seen a MAF on any car that wasnt simple to just replace.
you have to disassemble the intake a little bit to access the MAF to clean it, dont bother. just replace it!!
oh and btw, all these engine cleaners seafoam techron etc do nothing either, except foul your plugs, or fry your o2 sensors,
or clog your cats. no way a prius needs any fuel system or top end cleanout. EVER.
synthetic oil like our prius uses keeps everything incredibly clean, and as long as you didnt fill your tank up with 5 yr old fuel mixed with water, the fuel system doesnt need any assistance either

 

I agree. At 180k I have never cleaned MAF and the car is driving perfectly fine.
I have always made sure the air filter is in proper order and is not leaking air around it though.

Alex

 

My first maf cleaning was at 155k. Since cleaning, I have only had a partial tank of gas, but there is no significant performance advantage noticeable, or at least nothing that is directly attributable to the maf. I cleaned the throttle body (using a method similar to Patrick), cleaned the maf, replaced spark plugs, and replaced the PCV. Since then I *may* be getting about 3%-5% better mileage (and I suspect that's not actually a result of those maintenance items).

As others have said, the maf is one of those things that should be touched sparingly. If it's not dirty, it's not worth touching.

 

I haven't touched the MAF on my Prius (100K miles) yet, but last year my old '98 Subaru (200K miles) started idling rough. I cleaned the MAF, and the idle smoothed out noticeably and immediately, got better highway performance, and has been running fine since. Maybe I'll do that again at 400K.

 

First, I think this subject might be one of those that there will be disagreement.

In my experience, while my Camry and Prius MAFs were easy to access and clean, the MAF on my decade-ago Ford Mustang was a bit of a PIA and the one on my son's Audi, which I showed him how to access and clean a couple of months ago qualified as one of the biggest PIA's in car repair that I have ever encountered.

That Audi took 45 minutes to access, one air box bolt lost somewhere in the bowels of the underhood, a stabbed and scraped knuckle or three, etc. Of course the actual cleaning took 30 seconds.



With my Camry, it has thrown bogus codes since I purchased it new in 2003. Toyota has replaced the ECU TWICE under warranty and has still never solved the problem, so I ignore the check engine on that car and instead rely on my years of working on cars and my imperfect memory and questionable mechanic's skills. The light usually stays on for about three days and then disappears, only to resurface three months later to repeat the cycle.

Still, when the car began to have idle and power problems, I immediately pulled and cleaned the MAF and problem solved.

When the Prius seemed to idle rough some 15K ago but no Check lights, I cleaned the MAF and throttle body and problem solved (in that case, may have been the TB, who knows.

All I do know is that I have cleaned the MAF on several different vehicles over the years and only noticed improvement, but I did not do it as a preventative measure....maybe that's the key.

 

I just cleaned my MAF sensor using CRC Mass Air Flow Sensor Cleaner @ 135K miles, let it dried completely before re-installing. It caused both the CEL (Check Engine Light) and Malfunction Indicator Lamp (MIL) to come on with a red car with icon on the top left corner on the MFD. I needed this fixed right away and decided it was this part causing the issue since I had no issues and test drove the car after making the spark plug and pcv valve replacement I did. I did want an original part so picked up my new MAF sensor from Toyota and was surprised that it cost $215. After I replaced the new part, the MIL light and red car with icon on the MDF went way but the CEL was still on. I read in blogs that once the identified issue(s) are fixed, it takes a few starts before the CEL goes off since the error is cleared from the car's computer. After the third or fourth start, when I was ready to take the car to Advance Auto Parts to get the car scanned for malfunction codes, the CEL was gone.
Moral of the story is that your MAF sensor may just get damaged when cleaning so be prepare; I've had low mileage per gallon issues w/ my 2006 Prius and thought this would help. I feel better now that I've replaced the MAF sensor and although expensive, I rather have the original part.
On the $117.60 for labor; that is preposterous; it takes about 5 minutes to change this part; there are only 2 screws holding the MAF sensor.

 

welcome and well done!