Mass Air Flow troubleshooting
#1
Mass Air Flow troubleshooting
Hey Guys,
I recently had the engine light come on. I took it to a friend to scan it and it came up with P0102 mass air flow code. The car had been hesitating while driving it at all different speeds the same time this happened.
I cleaned the sensor and it was fine for a few days then it happened again and the light came back on. Same code the second time.
I found some troubleshooting tips on google and tried them out. I back pinned the connector and ran the car. From pins B and C I had 1.300 volts and while tapping the reading changed to 2.5 volts. From what I read it should be 2.5 volts at idle.
I did this at idle and while reving the engine. The reading changed when I did that sporadically. It actually went backwards at one point, started at .877 volts and went down to .465 volts. Im pretty sure the MAF is faulty but I know there is a cleaning cycle which I would like to check before I spend $250 on a new one and it doesn't work.
Anyone have any more troubleshooting tips or does anyone know how to check the cleaning cycle? I assume its a relay somewhere to test?
Thanks for the help guys.
I recently had the engine light come on. I took it to a friend to scan it and it came up with P0102 mass air flow code. The car had been hesitating while driving it at all different speeds the same time this happened.
I cleaned the sensor and it was fine for a few days then it happened again and the light came back on. Same code the second time.
I found some troubleshooting tips on google and tried them out. I back pinned the connector and ran the car. From pins B and C I had 1.300 volts and while tapping the reading changed to 2.5 volts. From what I read it should be 2.5 volts at idle.
I did this at idle and while reving the engine. The reading changed when I did that sporadically. It actually went backwards at one point, started at .877 volts and went down to .465 volts. Im pretty sure the MAF is faulty but I know there is a cleaning cycle which I would like to check before I spend $250 on a new one and it doesn't work.
Anyone have any more troubleshooting tips or does anyone know how to check the cleaning cycle? I assume its a relay somewhere to test?
Thanks for the help guys.
Last edited by relaxo; 07-27-2010 at 03:29 PM. Reason: wrong scan code.
#2
Go to a junkyard and pull a couple of used ones for $15 bucks or so like i did. Even if you get 1 or 2 bad ones right off the bat...which is unlikely you've still have only spent 30 bucks or so. If you're not near a pick & pull junkyard than hit up Ed Morad for a used one.
#5
Thanks dude
#6
so i figured out why I was getting bad readings. I should have started with checking for power once the voltage was wrong, but I overlooked it.
There is a engine devices 10A fuse under the hood. I found it blown today when i double checked my work. The voltage measurements are bang on now.
If you are looking for correct voltage from the MAF:
1. Remove the connector and measure between pins. You should find 12 volts with the key ON and the car not running.
2. Next reconnect the connector and back pin it.
3. Start the car and measure between pins. You should find about 2.5 volts while its running. I got 2.750 volts.
4. Tap the MAF lightly while measuring. There should be no change in the reading. ( mine actually went to 2.8, but holding 2 meter probes in 1 hand while tapping with the other is probably the reason for the small jump)
5. If it fluctuates the MAF is most likely bad. There is another test you can do on the MAF but it requires test equipment.
Hope this helps should anyone else have issues like I did. My car seems to be running fine now. If the fuse blows again i guess I'll have to dig for a bad wire.
There is a engine devices 10A fuse under the hood. I found it blown today when i double checked my work. The voltage measurements are bang on now.
If you are looking for correct voltage from the MAF:
1. Remove the connector and measure between pins. You should find 12 volts with the key ON and the car not running.
2. Next reconnect the connector and back pin it.
3. Start the car and measure between pins. You should find about 2.5 volts while its running. I got 2.750 volts.
4. Tap the MAF lightly while measuring. There should be no change in the reading. ( mine actually went to 2.8, but holding 2 meter probes in 1 hand while tapping with the other is probably the reason for the small jump)
5. If it fluctuates the MAF is most likely bad. There is another test you can do on the MAF but it requires test equipment.
Hope this helps should anyone else have issues like I did. My car seems to be running fine now. If the fuse blows again i guess I'll have to dig for a bad wire.
#8
So I was having bad hesitation and found that the MAF sensor was cracked around the base of the female connector and allowed the pins not to get a connection (so basically unplugged). Superglued plastic connector back together and runs much better. Meanwhile my codereader came in the mail and I now get a P0102 low voltage error even after reset. I do have an aftermarket cold air intake installed... could this give me the error for too much airflow? I should probably check the voltage... 2.5V is what I'm looking for I guess.
#10
I do have an aftermarket cold air intake installed... could this give me the error for too much airflow? I should probably check the voltage.