What are the properer Ohm (resistance) readings on MSP's Mass Air Flow seonsor?

pomidor

Member
Contributor
:
2003.5 mazdaspeed protege
I'm trying to figure out if my Mass Air Flow sensor on my MSP is faulty or not.

I read that measuring the resistance on MAF pins with an Ohm meter can yield some useful results (if one knows what they mean), except that I don't know which pins on the MAF to test, with which terminals (black/red) on the multimeter, and what resistance to expect from each test.

I did some poking around in this forum, but I couldn't find anything comprehensive enough to be of help.

Anyone know anything about this?

I'm attaching a picture of my MAF (removed). The way I positioned it: Air flows in from the left and out the right of it. MAF is right side up. Pretend you're looking at it while sitting in the drivers seat.

View attachment 175851
 
factory manual says to check the voltage by using the OBD reader. it also gives ways to check for open/closed circuits, but nothing about the normal resistances... as far as i can tell...
 
It's been suggested to me that my MAF sensor if faulty (car stalled and jerked when accelerating), but I wanted to make sure first before committing to buying a new one, especially given that I had no CEL light telling me that anything is wrong with the sensor.

I googled for "how to test the sensor". I came across some video of some guy measuring the resistance on some of the pins on the MAF. I figured I'd do the same, but I needed to know what the expected reading would be for MSP.

Anyway, I cleaned the sensor with MAF Cleaner. Although I have no clue what the resistance reading are supposed to be on this sensor, they were quite different before and after the cleaning.

And it looks like the cleaning did the job. Car runs fine now.

BTW, I didn't know OBD readers can tell you more about the MAF Sensor than just the usual ("it caused the CEL to come on"). My OBD reader definitely doesn't, then again, didn't pay much for it so I'm not surprised it does just the bare minimum.

Thanks for the reply
 
you have to have the sensor monitors. i think it can tell you both the measurement in g/s and the voltage, although its possible you need a breakout box to measure the voltage. now i cant remember.
 
There is more to it but this is what the service manual states:

TERMINAL: 88
SIGNAL: MAF
CONNECTED TO: MAF sensor
TEST CONDITION:
Ignition switch ON 0.9—2.0 VOLTS

Idle 1.7—2.4 VOLTS

ACTION:



Inspect MAF sensor

(See 01–40B–28
MASS AIR FLOW
(MAF) SENSOR
INSPECTION [FS])
Inspect related harness

 
Last edited:
Where did you guys get the service manual from? Is there a link to it?
 

New Threads

Back