MAF problems
21 April 2009, 01:45 PM
#1
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MAF problems
hi, unplugged my maf today with the engine running, it kept running but very rough i assume this means that the MAF is fubard? the car is 94wrx with the green label MAF can i only use a green label for a replacemant? thanks.
21 April 2009, 02:16 PM
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AFAIK the engine stalling when removing the MAF sensor doesn't 100% indicate the MAF is knackered. Mine will keep running although very rough (rise and falls) and the monitor will throw up an error code 23 so it knows when its not there. Hot or cold.
This is on MY00 though.
This is on MY00 though.
21 April 2009, 02:19 PM
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AFAIK the engine stalling when removing the MAF sensor doesn't 100% indicate the MAF is knackered. Mine will keep running although very rough (rise and falls) and the monitor will throw up an error code 23 so it knows when its not there. Hot or cold.
This is on MY00 though.
This is on MY00 though.
21 April 2009, 04:31 PM
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My MY99 was hunting when hot, and the maf was plugged in. When unpluging it, i found it would idle better when warm. I changed the maf, and it was fine.
My symptoms were exaggerated as i had a cold fault with the icv too.
My symptoms were exaggerated as i had a cold fault with the icv too.
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21 April 2009, 11:38 PM
#10
u never know!
22 April 2009, 11:57 AM
#15
Doh! 
Not sure mate... What about letting car idle steady after warmed up and probing each pin. if you get a reading of about 1.0 - 1.2V then that will prob be it. If you then get someone to rev the car a bit and the reading rises and falls in concert with the revs then it's defo the output voltage pin-out... 
Last edited by joz8968; 22 April 2009 at 12:01 PM.
22 April 2009, 10:23 PM
#16
im sure theres alot of people with much more knowledge than me on here about the electrical system,electrics not really my thing,sorry i cant be of much help joz.worth getting a new thread up?
22 April 2009, 11:09 PM
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22 April 2009, 11:23 PM
#18
24 April 2009, 08:23 PM
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measured the voltage of the MAF sensor and they are as follows
0.3v ing on
1.0v @ idle
4.85v @ full throttle
so from the first 2 readings it is in spec what about the 4.85v at full throttle is this in spec?
cheers.
0.3v ing on
1.0v @ idle
4.85v @ full throttle
so from the first 2 readings it is in spec what about the 4.85v at full throttle is this in spec?
cheers.
- can't remember tbh. 
28 April 2009, 09:45 AM
#28
With engine up to temp and idling, probe the wires until you get a Volt reading. It'll either be about 1V or 5V (can't remember if the later MAF's voltage is 'reversed'). Then run the voltmeter into the cabin and rev the car to near max revs. If the voltmeter rises and falls (or falls and rises) with the revs, then that's the signal wire.
Report back with your Volt readings at what revs, and we'll tell you if it's okay, etc...
Report back with your Volt readings at what revs, and we'll tell you if it's okay, etc...
Last edited by joz8968; 28 April 2009 at 09:46 AM.
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