MAT Secnsor

[taksepidar]

As some of you may know from my previous post I have Bad fuel Economy in my car , I Replaced O2 sensor but still, Today I checked MAT (Air Temperature Sensor) sensor and found infinite resistance, can it be the problem? as I know MAT sensor have minor effect. -

I check manual and it said for 25-30 Degree sensor should read 2.2-2.8 Kohm So for testing is it good idea to replace sensor with 2.5 Kohm Resistor?

Today I couldn't find airflow sensor in my Daewoo Cielo SOHD 97? also I couldn't find it in my manual. does any body know is it possible? a car without Airflow sensor?

Have nice weekend
John

[daewoomofo]

if yor going to replace it with a resistor, replace it with one with more resistance than 2.5k ohms. if you drive on a day that is cooler than 25-30 degrees you will run lean and risk detonation which will damage your pistons. but the correct way to fix the problem is to get a new sensor.

[Daniel]

Cold air intake = high electrical resistance at sensor = rich mixture. You sould get a error code 25 with a open sensor.

There is no air flow sensor. The MAP (manifold absolute pressure) sensor is used instead.

Daniel

[taksepidar]

So I think 3K ohm is good (20-25 Degree) should be fine for here, I am in Australia in the begining of summer

But my check engine light is ok
should I Scan it for error? have you got any Idea where to buy MAT?

thanks
john

[PrecisionBoost]

MAT/IAT sensor is used in conjunction with the MAP sensor to figure out the density of air

Then RPM is used to calculate a "speed density" value that corresponds to the mass air flow entering the intake.

If your temp sensor is infinite (open) then it will make the ECU inject more fuel ( since colder air is denser than warm air ..... and therefore you have more air so you need more fuel to make the air/fuel mixture 14.7:1 )

So..... short answer.... yes.... dropping 3K resistor in there will work just fine for now.... it's certainly better than running it with a damaged sensor.


As for the sensor itself, there really isn't a whole pile of difference between temp sensors on different cars..... personally.... I'd simply get one out of a wrecked Astra or Corsa (hopefully same connector) and drop it in.

If the new sensor resistance is off a bit odds are it's not going to make much all that much of a difference.

You could allways go to the autowreckers and check the resistance to see how close it is (for example... if 3Kohms = 20 degrees ... then go out to the wrecker on a 20 deg day and find a sensor that reads 3K accross it's terminals )

[taksepidar]

Yes...
thank you
I replaced 2.8K with 3.3k( it is usually 14-18 C these day) and in two days I can notice the differnce( how much money I lost during last year)
when I get time I will buy a second hand thank you again
John