What is air flow meter on a car?

I have no idea what this is. I have a Toyota Rav4 and the dealer is telling me that I need to change the air flow meter because gas is not getting to the engine. Does this sound right?


How much does it typically cost?

7 Answers

  • Anonymous
    1 decade ago
    Best Answer

    the air flow meter is used by the computer to determine the amount of air entering the engine so it can provide an appropriate amount of fuel. the most common problem with these is that the sensing or hot wire that is used to measure the air flow gets coated with dirt and this insulates the wire causing the reading to be skewed. this causes the computer to supply either too much or too little fuel. the oxygen sensor then reports the problem and the check engine light is turned on. if you want to save money, the sensor may work fine if it's cleaned. you can request that they do it, but they probably won't, or you can take it to an independent shop where we clean these on a regular basis. if it doesn't work then you can have it replaced.

    if your problem is just a check engine light and it has no apparent running problems, cleaning should work. if it is running bad you may want to go ahead and replace it.

    Source(s): ASE master tech
  • Mack
    Lv 5
    1 decade ago

    The air flow meter is a sensor that tells your on-board computer how to run your engine, along with several others. If a dealer tells you something like this, they probably have connected a computer to it to see what the 'code' is with the problem. Codes can sometimes be deceptive. If it's under warranty, let them fix it. If not under warranty, find a good mechanic that will explain how it works. It takes a process of elimination to actually determine what makes your 'Rav4' , or any car with CC equipment, run correctly. However, if your dealer told you this and you, along with 'your' mechanic think it is the problem, let 'your' mechanic fix it. It's just a small sensor that gets taken out, then a new one put in ... it's a screw-type assembly.

    You might get lucky and find a very good mechanic not working at a dealership, good luck, Mack

  • 1 decade ago

    Air flow meter measures the amount, temperature and pressure of air coming into the engine through the intake, and thus tells the computer how much fuel to give the engine. It is very possible that a broken AFM would cause no fuel to go to the engine but that doesn't seem to me personally to be the likeliest choice. I would want to check other things first. AFM's are usually pretty reliable, too. I would get a second opinion. Hope this helps

    Source(s): backyard mechanic
  • gudiel
    Lv 4
    3 years ago

    A mass airflow sensor is used to verify the mass of air entering an electronically gas-injected engine. The air mass suggestions is needed for the engine administration unit (ecu) to calculate and grant the right gas mass to the engine. An air bypass meter, additionally understand as air intake meter, is a gadget that measures how plenty air is flowing with the aid of a tube. It would not degree the quantity of the air passing in the process the tube, it measures the quantity of mass flowing in the process the gadget in a defined time section. So, an air bypass meter is purely an application of mass bypass meters for a undeniable medium.

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  • Anonymous
    1 decade ago

    There are many different types of air flow meter but they all do the same job, that is to measure the amount of air entering the engine in order for the computer to work out how much fuel it neads to inject into the cylinders for a near perfect fuel/air ratio of 14:1.

    Source(s): Master Mechanic 24 Years. I think tigga neads to go back to trade school as a PCV (positive crankcase vaccuum valve) has nothing to do with the airflow meter.
  • 1 decade ago

    Yes the dealer is particially right but dont let anything or anyone tell you change something because this is what they think could fix the problem...Know this just because the air flow meter or better known as the pcv regulates the amount of air pressure which causes gases to breath throughout your intake and make your car/truck go zoom. Doesn't mean you have found the answer to your solution..However as a friend and maintenance guy myself I would suggest you to stop by your local friendly neighborhood autozone, autoparts store and have them to research it for you if you really want to buy one.But the question should be "WHY AM I BUYING SOMETHING THE DEALERSHIP SHOULD AND COULD REPLACE ACCORDING TO THE WARRANTY OF MY VEHICLE!" Besides, you can google research this part online and input your make, model and year of vehicle and it will gradually show you a picture or diagram of how the air intake/airflow system for your vehicle should look like.

    Take care and drive safe!


  • Anonymous
    1 decade ago


    Yes it could effect many things , if defective your car doesnt think its getting air and will adjust timing , sometimes to such an extreme that it cuts back fuel supply , without proper fuel in the combustion chamber can lead to detonation.


    Source(s): buy one and install it isnt hard at all , here is one on ebay http://cgi.ebay.com/ebaymotors/Air-Flow-Meter-RAV4...
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