Help! mass airflow sensor

HEXABOT

New Member
Jul 8, 2019
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LOS ANGELES
Well I don't really know if its the M.A.S. I will explain my problem now:

When I accelerate the car start to hesitate like its low of fuel but only when its waiting at a red light, I guess that was the air filter so I change it for a new one, after I try the car without the air filter and works well no hesitate or jerk even at a red light, then I put the new filter and the same problem comes. some one told me that can be that the mass airflow sensor could be dirty.

what do you think?

thanks for reading my post.

also there's a video in you tube of my problem

View: https://youtu.be/fA-O3163a7I
the problem with air filter

View: https://youtu.be/k-FEwjHBI7k
with out air filter
 
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wmburns

SN Certified Technician
Aug 14, 2009
5,598
464
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Houston Texas
It is always a good idea (and can't hurt anything) to clean the MAF sensor. Always use a product designed for the job. The MAF sensor is easily damaged.

Do you have an ODB2 scanner? If you did, having access to operational PID's might make short work of your problem.

ForScan ODB2 scanner w ELM327 USB
 

ReefBlueGT

New Member
Oct 4, 2018
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FWIW, I recently cleaned mine in a 93 5.0, and the car definitely runs smoother now. I couldn't tell how dirty it was before cleaning it, but once I had sprayed it down and let it dry, it was apparent that it had been pretty filthy, since the wires on the sensor looked much smaller and pristine afterwards. There was also a film on the mesh screen in front of the sensor. Wasn't having significant driveability problems, but it's a cheap and easy thing to do, and can't hurt - just make sure you do it properly. I took out the entire metal piece between the filter box and the intake hose to the manifold when I did mine. That's how you can properly clean and flush it out while it's off the car, including that screen, and since you aren't removing the sensor by itself, I think it's safer.
 

HEXABOT

New Member
Jul 8, 2019
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LOS ANGELES
Thanks I did that I buy the maf cleaner spray but it continues with the problem, also when the car is on I unplug the MAF sensor and the car keep working I saw on youtube that its suppose to turn off when its unplugged. I will buy the maf sensor it seems that's the only solution.

thanks for the answers
 

wmburns

SN Certified Technician
Aug 14, 2009
5,598
464
164
Houston Texas
I unplug the MAF sensor and the car keep working I saw on youtube that its suppose to turn off when its unplugged
Not true. Unplugging a MAF sensor will not make the car stop. If unplugged the PCM will substitute default values based upon other sensor values. In fact, unplugging the MAF is a valuable trouble shooting tool. If for example unplugging the MAF makes it run better, THEN this means there is some issue with the MAF.
 

Danny2v

Member
Jun 24, 2019
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Not true. Unplugging a MAF sensor will not make the car stop. If unplugged the PCM will substitute default values based upon other sensor values. In fact, unplugging the MAF is a valuable trouble shooting tool. If for example unplugging the MAF makes it run better, THEN this means there is some issue with the MAF.
Although you are right about unplugging being a great way to diagnose, it does not mean that the MAF is automatically bad. Unplugging the sensor puts the car into open loop which stops using the MAF, O2, and all other monitors... So if you unplug and see it runs better, the next step is to figure out which sensor exactly is bad